Caribbean - Central America Weather

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cycloneye
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Re: Caribbean - Central America Weather

#21081 Postby cycloneye » Tue Jan 31, 2023 7:02 am

Area Forecast Discussion
National Weather Service San Juan PR
521 AM AST Tue Jan 31 2023

.SYNOPSIS...Moderate to fresh northeast trades due to a surface
high over the western Atlantic will continue to promote breezy
conditions and choppy to hazardous wind-driven seas for the next
few days. Life-threatening rip currents will persists across the
north and east facing beaches of the islands through midweek.
Passing trade wind showers will prevail through the end of the
week, with minor rainfall accumulations in general.


&&

.SHORT TERM...Today through Thursday...

Variable weather conditions are expected today across the islands,
mainly across the northern and eastern portions of Puerto Rico, and
the USVI in the morning hours. The main hazards across the islands
continue to be choppy to hazardous seas across the Atlantic waters
and Passages until the end of the period. In addition, life-
threatening rip currents will continue along the north and east
facing beaches of the islands until the end of the workweek. For
today, the shower activity should be less than the previous days due
to dry air present across the local area. This weather pattern will
persist for the next few days. A broad mid level high pressure will
be the dominant weather feature and is expected to continue
promoting drier air across the region. For the rest of the period,
fragments of moisture will be carried by the trades, resulting in
passing showers overnight and during early morning hours across the
windward portions of the islands. During the afternoon hours,
convection still possible to occur across the western to
southwestern portions of Puerto Rico leaving minor rainfall
accumulations. Temperatures across the islands are expected to be
normal to below due to the northeast winds.

.LONG TERM...Friday through Tuesday...

A weak surface high pressure over the central Atlantic will be
replaced by a stronger high pressure on Sunday. In response,
winds will shift from the east to east-southeast and become
moderate to fresh once again later in the weekend. At upper
levels, a ridge west of the region is expected to shift east of
the Leewards by Sunday, as a long wave trough moves slowly
eastwards from the west through the rest of the long term period.
The 500 mb temperature is forecast to drop to around -10 degrees
Celsius during this period, increasing instability aloft.

From Sunday through Tuesday, weak trade wind perturbations will
stream across the islands during the morning hours, increasing
shower activity in early morning convection between the USVI and
eastern PR, followed by afternoon showers over western PR.
Rainfall amounts are expected to remain under an inch, but will
continue to monitor and adjust the forecast as needed during the
next couple of days.


&&

.AVIATION...Mainly VFR conditions are expected to prevail across all
terminals during the next 24 hrs. Fast moving trade wind showers may
cause brief MVFR cigs at TJSJ/TIST/TISX btw 10z-22z. Winds will
continue from the NE at 10-18 kts with higher gusts after 31/14Z.


&&

.MARINE...Choppy to hazardous seas between 5 and 8 feet will
continue through midweek due to a fading northeasterly swell and
wind-driven seas. NE winds at 15-20 kt with higher gusts will
prevail for the next couple of days, and SCAs are in effect for
most of the local waters.

Across the northwest to northeastern beaches of the islands there
is an elevated risk of rip currents, and a High Rip Current Risk
remains in effect for northern PR, Culebra, and St. Croix. Please
refer to the latest Coastal Hazard Message (CFWSJU) and Surf Zone
Forecast (SRFSJU) for detailed information.


&&

.SJU WATCHES/WARNINGS/ADVISORIES...
PR...High Rip Current Risk through late Thursday night for PRZ001-002-
005-008.

High Rip Current Risk through Wednesday afternoon for PRZ012.

VI...High Rip Current Risk through Wednesday afternoon for VIZ002.

AM...Small Craft Advisory until 8 PM AST Wednesday for AMZ710-712.

Small Craft Advisory until 2 PM AST Wednesday for AMZ715-741.

Small Craft Advisory until 2 PM AST this afternoon for AMZ722-
732.

Small Craft Advisory until 2 AM AST Wednesday for AMZ742.

&&

$$

SHORT TERM/AVIATION...GRS
LONG TERM/MARINE...DSR
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Re: Caribbean - Central America Weather

#21082 Postby cycloneye » Wed Feb 01, 2023 4:58 am

Area Forecast Discussion
National Weather Service San Juan PR
359 AM AST Wed Feb 1 2023

.SYNOPSIS...Moderate to locally fresh northeast winds will persist
for the next few days. Choppy to hazardous wind-driven seas will
improve by Friday. Life-threatening rip currents are expected to
continue across the north and east facing beaches of the islands
today and for northern PR on Thursday. Passing showers will
continue to move at times across the islands during the next
several days.


&&

.SHORT TERM...Today through Friday...

Local weather conditions remain variable with below than normal
moisture. During the early morning hours, fast moving passing
showers are expected to affect the northern, eastern, and central
portions of Puerto Rico, and the USVI. However, drier will take
place and more stable conditions will persist during the daytime
hours across much of the local islands. The main hazards across the
islands have not changed form the previous discusion. Choppy to
hazardous seas across the Atlantic waters and Passages will continue
until Thursday night and diminishing by early Friday. In addition,
life-threatening rip currents will continue along the north and east
facing beaches of the islands (except Saint Thomas and Saint
John) until the end of the workweek. A broad mid-level high
pressure continues to dominate the weather conditions across the
Caribbean, promoting drier air across the region. As a result,
northeasterly winds will bring fragments of moisture embedded in
the trades, resulting in passing showers overnight and during
early morning hours across the windward portions of the islands.
This weather pattern is forecasted to persist for the next several
days. During the afternoon hours, the potential for convection
remains possible to occur across the western to southwestern
portions of Puerto Rico leaving minor rainfall accumulations.
Temperatures across the islands are expected to be normal to below
due to the northeast winds. Overall, maximum temperatures will be
in the low to mid 70s across the higher elevations to the mid 80s
in coastal areas.

.LONG TERM...Saturday through Wednesday...

A mid-level ridge over the region will shift to the northeast of
the northern Leewards during the weekend, as a long wave trough
presses against it from the west. In response, the 500 mb
temperature drops to near -9.5 degrees C by Sunday. Meanwhile, a
broad surface high pressure will move off the US East Coast and
build over the north-central Atlantic by Monday. At least through
Monday, a moderate to locally fresh east to southeasterly wind
flow should prevail across the area. Weak trade wind perturbations
will move at times from the east, increasing showers across the
USVI and eastern sections of PR during the overnight/early morning
hours, followed by diurnally induced afternoon showers over
western PR. By Wednesday, a TUTT low is expected to develop from
a polar trough to our northeast, while an associated surface front
lingers around 25N. This will relax the pressure gradient briefly
and allow for better low-level moisture to pool over the area.


&&

.AVIATION...Mainly VFR conds expected to prevail across all
terminals during the next next 24 hrs. Quick passing trade wind
showers over the waters push onshore for northern USVI and PR,
with limited operational impacts expected at TJSJ/TIST/TISX btw
10Z-22Z. Winds will continue from the NE at 12-18 kts with
stronger gusts after 01/14Z.


&&

.MARINE...Seas are expected to gradually subside below SCA criteria
by tonight. But overall choppy seas will persist across the
offshore waters and local passages through late Thursday, before
becoming hazardous once again late in the weekend into next week
due to increasing trades and a northerly swell. A high risk of rip
currents continues for the eastern and northern beaches of Puerto
Rico, Culebra and St. Croix.


&&

.SJU WATCHES/WARNINGS/ADVISORIES...
PR...High Rip Current Risk through late Thursday night for PRZ001-002-
005-008.

High Rip Current Risk through this afternoon for PRZ012.

VI...High Rip Current Risk through this afternoon for VIZ002.

AM...Small Craft Advisory until 8 PM AST this evening for AMZ710-712-
741.

&&

$$

SHORT TERM/AVIATION...GRS
LONG TERM/MARINE...DSR
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Re: Caribbean - Central America Weather

#21083 Postby cycloneye » Thu Feb 02, 2023 4:43 am

Area Forecast Discussion
National Weather Service San Juan PR
455 AM AST Thu Feb 2 2023

.SYNOPSIS...

Variable weather conditions will continue to persist across the
local area for the next couple days. The weekend, however, will
observe a changing weather pattern as the mid-level ridge
weakens, a weak upper-level trough develops and low-level
moisture content increases across the local islands. Choppy seas
will continue across the local nearshore and offshore waters for
the next several days. High rip currents will continue today for
the northern and eastern beaches of Puerto Rico.


&&

.SHORT TERM...Today through Saturday...

A mid-level high pressure will promote subsidence and dry air
intrusion aloft through early this weekend. This mid-level high
begins to weaken its influence over the Northeast Caribbean by
Saturday, as GFS and ECMWF both suggest. A surface high pressure
drifting eastward across the Atlantic Ocean will promote a trade
wind flow with the typical cool temperatures for February across the
islands. Although we expect a mixture of sunshine and clouds today
and tomorrow, occasional trade wind showers will arrive each day
across the north, central, and eastern sections, enhanced overnight
and early in the morning due to cool air advection.

Suppose model guidance is on the right track, and the trade wind
inversion weakens on Saturday. In that case, a surge of moisture may
result in showery weather on the seasonal pattern, consisting of
passing showers across the north and east sections of Puerto Rico
and the Virgin Islands in the overnight and morning hours, followed
by afternoon convection across western PR by the mid-morning into
the afternoon. We do not anticipate widespread significant rainfall
amounts. Still, ponding of water in poorly drained areas and
isolated urban flooding could be possible due to periods of moderate
to locally heavy rains.


.LONG TERM...Sunday through Thursday...

At upper-levels, a short-wave trough will settle west of the islands
while the mid-level ridge continues to move northeast of the
forecast area, weakening the trade wind cap on Sunday. This will
promote 500 mb temperatures to drop close to -9.5C. With this
setup, conditions aloft could be somewhat conducive for deep
convective activity. At low-levels, a surface high pressure well
north in the Atlantic will strengthen, intensifying the pressure
gradient across the northern Caribbean. Trade winds, therefore,
are forecast to intensify while advecting low-level moisture over
the islands, maintaining moisture content at near normal to
slightly above normal for this time of year. Consequently, Sunday
is expected to be the wettest day of the long-term period. The
limiting factor will be any dry air intrusion at mid-levels. For
now, both global models suggest showery weather during morning
hours across eastern portions of the islands. These showers will
promote at most ponding of water in roadways and in poor drainage
areas.

In the afternoon, surface heating and local effects will focus the
activity across western/northwestern Puerto Rico. Isolated
thunderstorms were included in the forecast given the below-normal
500 mb temperatures expected for that day. However, any
thunderstorm activity will be brief and, due to fast steering
winds, move offshore fairly quickly. Nevertheless, urban and small
stream flooding are possible in isolated areas. For early next
week, a seasonal weather pattern is expected with a prevailing
east southeast wind pattern. However, by midweek, models are
suggesting slightly unsettled weather conditions once again as
another shortwave trough at upper levels develops northwest of the
forecast area. Shower activity are once again expected to
increase for the latter part of the forecast period.


&&

.AVIATION...
(06Z TAFS)
Issued at 413 AM AST Thu Feb 2 2023

VFR conditions will persist most of the time, but the NE winds will
bring quick -SHRA/SHRA over PR/USVI and may impact windward
terminals. This activity may reduce VIS briefly and result in BKN
ceilings between FL030-050, with limited operational impacts. Winds
will continue from the NE/ENE at 5-15 kt thru 02/13, increasing to
around 15-20 kt with stronger gusts and sea breeze variations
afterward.

&&

.MARINE...

Moderate to fresh northeast winds will maintain choppy marine
conditions for small craft until Saturday. Winds will increase on
Sunday reaching 20-25 knots across the local nearshore and
offshore waters. Therefore, hazardous marine conditions will
return once again by the end of the weekend into early next week.
A high risk of rip currents continues for the eastern and
northern beaches of Puerto Rico through late tonight.

&&

.SJU WATCHES/WARNINGS/ADVISORIES...
PR...High Rip Current Risk through this afternoon for PRZ001-002.

High Rip Current Risk through late tonight for PRZ005-008.

VI...None.
AM...None.
&&

$$

SHORT TERM...CAM
LONG TERM....CVB
AVIATION...CAM
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Re: Caribbean - Central America Weather

#21084 Postby cycloneye » Fri Feb 03, 2023 5:03 am

Area Forecast Discussion
National Weather Service San Juan PR
502 AM AST Fri Feb 3 2023

...New SYNOPSIS, AVIATION, MARINE...

.SYNOPSIS...

A variable weather pattern will prevail today, with periods of
partly cloudy skies and passing showers at times. This weekend,
and afterwards, a changing weather pattern will take place as
winds shift out of the east southeast and moisture content over
the islands increases. Marine and coastal conditions will turn
hazardous once again by Sunday into early next week.


&&

.SHORT TERM...Today through Sunday...

The east-northeast winds will bring a fragment of moisture across
the islands resulting in brief passing showers today, but in
general, we expect a mixture of sunshine and clouds. The mid-level
high pressure continues reinforcing a trade wind cap, subsidence,
and dry air intrusion aloft. Therefore, shallow convective
instability will prevail throughout the day.

The mid-level high mentioned above will begin to weaken as its moves
eastward away from the islands eroding the trade wind cap from
Saturday onward, which may favor vertical mixing. In addition, GFS
suggests a jet stream approaching/or moving closer to the Northeast
Caribbean Saturday and Sunday. While a plume of moisture, advected
by the easterlies, will provide favorable conditions for showery
weather throughout the weekend. Rain activity will be focused across
the east half sections of PR and the U.S. Virgin Islands and should
propagate into the western half of PR by the afternoon. Isolated
thunderstorms were included in the grids, particularly for Sunday,
as the Galvez-Davison Index (GDI) suggests atypical high values for
February. Another factor in having thunderstorms in our forecast was
the cooler-than-normal temperatures at 500 MB. We do not anticipate
widespread significant rainfall amounts, but ponding of water in
poorly drained areas would be possible due to periods of moderate to
locally heavy rains.



.LONG TERM...Monday through Friday...

The long-term pattern is now looking wetter for the most part. At
low-levels, patches of moisture embedded in the east southeast
trades will cross the islands in a frequent manner maintaining
above normal moisture content over the forecast area. Dynamically
speaking, a series of short-wave troughs and cold air advection at
mid to upper levels will support unstable weather conditions
resulting in the potential for deep convective activity. Monday
looks to be the driest of the long-term period as dry air intrusion
at mid-levels will sustain mostly shallow convection across the
islands. Still, showers over eastern portions of the islands during
the morning hours and afternoon rainfall activity across western
Puerto Rico can be expected.

For the rest of the workweek, available moisture and favorable
dynamics will support variable weather conditions with showery
weather pattern at times throughout the day and enhanced activity in
the afternoon over interior and western Puerto Rico. The second
half of the week, particularly Thursday and Friday, looks to be
more active in the afternoons as 500 mb temperatures drop below
-10 C and jet dynamics at upper-levels turns favorable for
divergence across the northern Caribbean. The GFS Galvez-Davison
Index indicates the potential for isolated thunderstorms with the
strongest convective activity. Overall, GFS suggests above normal
amounts of precipitation for the month of February, mostly for
eastern and western Puerto Rico, Vieques, Culebra and the
northern U.S. Virgin Islands, particularly St. Thomas and St.
John. The ECMWF has a drier solution but still shows above normal
precipitation for the eastern third of the forecast area
throughout the week. In general, ponding of water in roads and
poorly drained areas are anticipated with this weather pattern
with the potential of urban and small stream flooding in areas
with the heaviest rainfall activity.


&&

.AVIATION...
(06Z TAFS)

VFR conditions will persist throughout the period with the arrival
of occasional quick -SHRA/SHRA over PR/USVI. Fragments of moisture
may briefly create BKN ceilings at FL030-FL070, and rain activity
may reduce VIS. Winds will continue calm-light/VRB thru 03/13,
returning from the E-ENE at 11-17 kt with higher gusts and sea
breeze variations afterward.

&&

.MARINE...

Choppy marine conditions will continue today and tomorrow.
However, building seas are forecast for Sunday turning marine
conditions hazardous once again as fresh to strong winds prevail
across the regional waters. Seas will increase between 8 to 10
feet by the end of the weekend into early next week, especially
across the offshore Atlantic waters. Moderate rip current risk
will prevail today and Saturday. But, coastal conditions will turn
hazardous as well by Sunday.


&&

.SJU WATCHES/WARNINGS/ADVISORIES...
PR...None.
VI...None.
AM...None.
&&

$$

SHORT TERM...CAM
LONG TERM....CVB
AVIATION...CAM
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Re: Caribbean - Central America Weather

#21085 Postby cycloneye » Sat Feb 04, 2023 6:32 am

Area Forecast Discussion
National Weather Service San Juan PR
515 AM AST Sat Feb 4 2023

.SYNOPSIS...

An increase in surface moisture and the weakening of the trade
wind cap will allow the formation of scattered to widespread
showers today and tomorrow. A drier air mass may reduce the amount
of rain activity by Monday. A transition to a somewhat unstable
weather pattern is possible from Tuesday onward due to a
meandering upper-level shortwave trough. Marine and coastal
conditions will deteriorate by Sunday into the workweek.

&&

...SHORT TERM...Today through Monday...

The short-term forecast continues on track. The mid-level ridge will
meander northeast of the Caribbean while an upper-level short wave
trough with axis west of the islands holds through early next week.
This will gradually weaken the trade wind cap that has been
influencing the area throughout the week and enhance vertical mixing
for the next couple of days. Models continue to suggest the cooling
of the 500 mb temperatures reaching minimum values of -10 C by
Sunday, further enhancing the potential for deep convective
development. In terms of moisture, breezy east southeast trades will
frequently advect fragments of moisture across the northern
Caribbean, increasing the precipitable water, 850-700 mb and 700-500
mb humidity to near normal and above normal levels between Saturday
and Sunday. Therefore, a wetter weather pattern will prevail this
weekend, particularly affecting portions of eastern/northwestern
Puerto Rico, Vieques, Culebra and the U.S. Virgin Islands.

Saturday will transition into this pattern as the trade wind cap
gradually erodes. Still, the windward coastal areas of the islands
will observe mainly brief passing showers in the morning before
afternoon scattered to numerous showers develop over the Cordillera
Central and western/northwestern Puerto Rico. Shower activity will
wind down during overnight hours. Sunday continues to be the wettest
day as upper-level conditions become more conducive for deep
convective activity while low- to mid-level moisture content peaks.
First, frequent passing showers, turning numerous at times, will
stream across eastern and northern coastal areas of Puerto Rico,
Vieques, and northern U.S. Virgin Islands during morning hours into
early afternoon. Some of these showers could even cause urban and
small stream flooding. In the afternoon, a more intense round of
showers will again affect interior and western/northwestern Puerto
Rico. GFS Galvez-Davison Index persists on having a few isolated
thunderstorms during this time. Given that favorable upper-level
conditions will be present for deep convection, thunderstorms were
included in the forecast. However, due to breezy wind conditions,
any activity will move offshore fairly quickly minimizing the flood
potential in those parts of the island. Nevertheless, ponding of
water in roads and poorly drained areas will promote poor driving
conditions in zones experiencing the heaviest rains.

Monday, looks to be the driest of the short-term forecast, primarily
because of a decrease in low-level moisture and dry air intrusion at
mid-levels. Quick passing showers, however, can still be expected at
times throughout the day.

...LONG TERM...Tuesday through Friday...

A short wave trough approaching from the northwest will somewhat
increase instability from Tuesday onward. A surface high pressure
drifting eastward across the Atlantic Ocean will tighten the local
pressure gradient inducing fresh to locally strong winds with the
arrival of normal to above-normal moisture content for most of
the long term. The instability created by this atmospheric
feature, combined with the surface moisture, will promote the
formation of periods of moderate to locally heavy rain, especially
Tuesday through Thursday.

Once again, model guidance suggests a drop in the 500 MB
temperatures and a jet stream aloft, favorable for the formation
of thunderstorms. In addition, the GFS Galvez-Davison Index
indicates above-average values for February, which may show the
potential for thunderstorms and widespread showers. Suppose this
weather pattern is on the right track. In that case, the above
normal-rainfall accumulations may be observed in the second part
of the work week, especially across eastern PR, the Virgin
Islands, and surrounding waters.

&&

.AVIATION...
(06Z TAFS)

Mainly VFR conds expected to prevail across all terminals during
the next next 24 hrs. Passing showers may move at times in and
around the USVI terminals and TJSJ through 04/14z. Moisture
increase may briefly create SCT-BKN ceilings at FL030-FL070
causing brief MVFR, but with limited operational impacts expected
at TJSJ/TIST/TISX btw 14Z-22Z. Winds will shift from the E-ESE at
12-18 kts with stronger gusts after 04/14Z.

&&

.MARINE...

Choppy conditions will continue across most of the local waters
today due to moderate to locally fresh easterly winds. Building
seas are forecast from Sunday onward, as a fresh to strong wind
easterly wind flow prevail across the regional waters. Seas will
increase up to 8 feet across most local waters and passages.
Therefore, Small Craft Advisories will be in effect from Sunday
into the workweek.

Beachgoers, there is a low to moderate rip current risk across
most locally exposed beaches today. The risk will increase to high
along the north and east facing beaches by Sunday.

&&

.SJU WATCHES/WARNINGS/ADVISORIES...
PR...None.
VI...None.
AM...Small Craft Advisory from 8 AM Sunday to 2 AM AST Tuesday for
AMZ710-722-741.

Small Craft Advisory from 8 AM Sunday to 2 PM AST Monday for
AMZ712-732.

Small Craft Advisory from 8 PM Sunday to 2 PM AST Monday for
AMZ715-725.

&&

$$

SHORT TERM...CVB
LONG TERM....CAM
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Re: Caribbean - Central America Weather

#21086 Postby cycloneye » Sun Feb 05, 2023 5:49 am

Area Forecast Discussion
National Weather Service San Juan PR
458 AM AST Sun Feb 5 2023

.SYNOPSIS...
Issued at 458 AM AST Sun Feb 5 2023

A surface high pressure will promote strong breezy conditions that
will carry a plume of moisture, creating showery conditions today.
Marine and coastal conditions will deteriorate from today onward.
A drier air mass will promote a mixture of sunshine and clouds
with a few passing showers on Monday. A meandering upper-level
shortwave trough will increase instability around mid-week,
followed by a building ridge by the end of the workweek into the
weekend.

&&

.SHORT TERM...Today through Tuesday...

A broad surface high pressure located over the central Atlantic
maintains the gradient tight, with strong breeze prevailing. The
steering flow at low levels will be out of the east-southeast at 22-
24 knots today. For tomorrow and Tuesday, the surface high is
expected to migrate eastward, and winds will relax a bit...out of
the east southeast on Monday at 16-20 knots, and around 15 knots on
Tuesday.

Recent satellite imagery shows an area of enhanced showers
approaching to the Leeward Islands, and should reach the area of
responsibility today. As a result, the high resolution and the
global models agree in passing shower activity during the day.
First, these showers should occur across the U.S. Virgin Islands and
eastern Puerto Rico, but as the day progresses, the showers should
spread into the interior and western Puerto Rico. Due to the strong
breeze, rainfall accumulations are not expected to be too high, but
they could lead to ponding of water on roadways and low-lying areas.

Monday looks a little drier, with the GFS-forecast sounding showing
a trade wind cap inversion around 925-850 mb, and precipitable water
values below one inch (below climatological values). Therefore,
limited shower activity is expected this day. On Tuesday, moisture
levels increase once again as another patch of moisture get dragged
by the trade winds. Scattered to numerous shower activity is
expected then, with wet roads early in the morning for the eastern
half of the forecast area.

.LONG TERM...Wednesday through Saturday...

Another surface high pressure drifting eastward across the
Atlantic Ocean will tighten the local pressure gradient generating
fresh to locally strong winds throughout the week. The wind flow
will advect patches around above-normal moisture content for most
of the long term. Instability may increase due to a meandering
upper-level shortwave trough and jet stream aloft Wednesday and
Thursday. The instability created by this atmospheric feature,
combined with the surface moisture, will promote the formation of
periods of moderate to locally heavy rain, especially Wednesday
through Thursday. Isolated thunderstorms were also included in the
forecast for these days due to a possible fall in the 500 MB
temperatures, a more favorable upper-level dynamic, and above-
average GFS Galvez-Davison Index values for February.

Stability may increase by the end of the workweek into the weekend
as a ridge pattern build at mid and upper levels, promoting dry
air and subsidence aloft. However, the east-to-east-southeast
winds will promote a typical rainfall pattern focusing on the
activity across eastern Puerto Rico and the Virgin Islands in the
overnight and morning and afternoon activity in the west/northwest
PR and downwind from the Virgin Islands next weekend.

&&

.AVIATION...
(06Z TAFS)
Issued at 458 AM AST Sun Feb 5 2023

Mainly VFR conditions expected to prevail through the forecast
period. Occasional passing showers are expected for the USVI and
TJSJ terminals trough the period with brief periods of reduced VIS
and low ceilings. Additional activity is also expected for TJBQ
after 17Z, as well as mountain obscuration across the Cordillera
Central. Winds will be out of the east at 22-26 knots with
stronger gusts.

&&

.MARINE...
Issued at 458 AM AST Sun Feb 5 2023

Fresh to strong easterly winds will create hazardous marine
conditions today, with seas between 6 and 8 feet with occasional
seas up to 10 feet, and a wave period between 6 and 8 seconds
across most of the local waters, where Small Craft Advisories are
in effect from this morning through at least early the workweek. A
northerly swell with a period between 10 and 14 seconds will
deteriorate even-more marine and coastal conditions Monday and
Tuesday. Hazardous marine conditions will continue through much of
the workweek.

Beachgoers, there is a high risk of rip currents along the north
and east-facing beaches of Puerto Rico and the easternmost
beaches of St. Croix today. Elsewhere, the risk is moderate.

&&

.SJU WATCHES/WARNINGS/ADVISORIES...
PR...High Rip Current Risk through late Monday night for PRZ001-002-
005-008.

VI...High Rip Current Risk through Monday afternoon for VIZ002.

AM...Small Craft Advisory from 8 AM this morning to 2 AM AST Tuesday
for AMZ710-722-741.

Small Craft Advisory from 8 AM this morning to 2 PM AST Monday
for AMZ712-732.

Small Craft Advisory from 8 PM this evening to 2 PM AST Monday
for AMZ715-725.

&&

$$

SHORT TERM...ERG
LONG TERM....CAM
AVIATION...ERG
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Re: Caribbean - Central America Weather

#21087 Postby cycloneye » Mon Feb 06, 2023 5:09 am

Area Forecast Discussion
National Weather Service San Juan PR
447 AM AST Mon Feb 6 2023

.SYNOPSIS...
Issued at 447 AM AST Mon Feb 6 2023

This week's main hazard will be the hazardous seas and life-
threatening rip currents along the Atlantic Waters/local passages
and north-facing beaches in the U.S. Virgin Islands and Puerto
Rico. Expect a mixture of sunshine and clouds today with a few
quick passing showers. A meandering upper-level shortwave trough
will increase instability around mid-week, followed by a building
ridge by the end of the workweek into the weekend.

&&

.SHORT TERM...Today through Wednesday...

A surface high pressure is currently located over the northeastern
Atlantic, maintaining winds out of the east southeast. The winds at
the low levels have weakened just a little bit, and breezy
conditions are expected to prevail through the forecast period. The
most recent satellite-derived precipitable water imagery shows a
drier air mass filtering over the region. As a result, limited
shower activity is expected today, but isolated to scattered
activity will remain possible...early in the morning for eastern
Puerto Rico and the United States Virgin Islands, and light to
moderate convection developing over western Puerto Rico in the
afternoon.

The patch of moisture that was supposed to reach the islands on
Tuesday is looking weaker in the latest guidance run, but still
precipitable water values are expected to climb up to more seasonal
values. As this low level feature moves in, the wind flow is
expected to shift from the east-northeast. Then, shower frequency
should increase across eastern Puerto Rico and the U.S. Virgin
Islands during the day, and with another round of showers developing
in the southwest in the afternoon. Significant flooding is not
expected with this activity, but wet roads and ponding of water in
low-lying areas can be expected.

On Wednesday, as a new surface high pressure rolls into the western
Atlantic, the gradient will tighten once again and winds will pick
up, with a steering flow out of the northeast at 18 to 20 knots. At
the upper levels, a trough will dig in, enhancing instability aloft.
Relative humidities are expected to be higher in the column, from
the surface to the mid and upper levels. As a result, the showers
could be a little bit stronger with the potential for isolated
thunderstorms to develop. A jet maximum is expected to remain just
southeast of the islands, enhancing the potential for additional
thunderstorms developing across the local waters at times.

&&

.LONG TERM...Thursday through Monday...

A meandering upper-level short wave trough and a jet aloft could
promote somewhat better upper-level dynamics across the Northeast
Caribbean. Once again, GFS and ECMWF suggest a drop in the 500 MB
temperatures with values around -10 or -11 degrees Celsius. The
jet stream is now (with the latest model cycle) more to the east-
southeast of the U.S. Virgin Islands, reducing the potential for
the formation of thunderstorms, but the potential remains present.
Stability may increase Friday through early Monday as a ridge
pattern build at mid and upper levels, promoting dry air and
subsidence aloft. At the surface, high pressure will move from the
U.S. Eastern seaboard to the Central North Atlantic Ocean,
tightening the local pressure gradient and generating breezy and
windy conditions throughout most of the second part of the week.
This surface high pressure will push a cold front southward but
off to the north of the islands (across the Atlantic Ocean),
leaving the islands at the mercy of the surges of moisture the
wind brings.

Consequently, expect breezy or windy conditions Thursday through
at least Saturday. The best chance (if any) to observe organized
convection through the long term will be on Thursday. Friday
onward, the east-to-east-southeast winds will promote a typical
rainfall pattern focusing on the activity across eastern Puerto
Rico and the Virgin Islands in the overnight and morning and
afternoon activity in the west/northwest PR and downwind from the
Virgin Islands.

&&

.AVIATION...
(06Z TAFS)
Issued at 447 AM AST Mon Feb 6 2023

Mainly VFR conditions expected to prevail through the forecast
period. Occasional SHRA moving between USVI and eastern PR could
through the day, but no significant impacts in operations are
expected. Additional activity expected after 17Z, for the western
Cordillera Central, with mountain obscuration. Breezy conditions,
with winds out of the ESE at 10-23 knots at FL050.

&&

.MARINE...
Issued at 447 AM AST Mon Feb 6 2023

The combination of wind-driven seas and a long-period northerly
swell will result in hazardous seas across the Atlantic Waters and
Caribbean Passages today and throughout the week. The northerly
swell will have periods between 11 and 15 seconds, and wave
heights between 6 and 10 feet across the Atlantic Offshore and
Caribbean Passages. The easterly winds will range between 15 and
20 knots. A surface low-pressure, now moving north-northeastward
across the Western Atlantic, will create a long-period northerly
swell forecast to arrive late Thursday night into Friday,
deteriorating marine and coastal conditions once again. These
factors will cause large breaking waves and rough surf conditions
along exposed north-facing beaches of the islands. Therefore,
Small Craft Advisories are in effect through mid-week and will
likely be extended throughout the rest of the week.

Beachgoers, life-threatening rip currents are likely across the
west, north, and eastern beaches of PR and the northern USVI.

&&

.SJU WATCHES/WARNINGS/ADVISORIES...
PR...High Rip Current Risk through late Tuesday night for PRZ001-002-
005-008-010-012.

High Surf Advisory until 6 PM AST Tuesday for PRZ001-002-005-008-
012.

High Rip Current Risk from this evening through late tonight for
PRZ013.

VI...High Rip Current Risk through late Tuesday night for VIZ001.

High Surf Advisory until 6 PM AST Tuesday for VIZ001.

High Rip Current Risk through this afternoon for VIZ002.

AM...Small Craft Advisory until 2 PM AST Wednesday for AMZ710.

Small Craft Advisory until 8 AM AST Tuesday for AMZ712-715.

Small Craft Advisory until 2 AM AST Tuesday for AMZ722.

Small Craft Advisory until 2 PM AST this afternoon for AMZ725-
732.

Small Craft Advisory until 2 PM AST Tuesday for AMZ741.

&&

$$

SHORT TERM...ERG
LONG TERM....CAM
AVIATION...ERG
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Re: Caribbean - Central America Weather

#21088 Postby cycloneye » Tue Feb 07, 2023 5:12 am

Area Forecast Discussion
National Weather Service San Juan PR
427 AM AST Tue Feb 7 2023

.SYNOPSIS...
Deteriorated and hazardous marine and coastal
conditions will continue due to winds and a northerly swell
spreading across the Atlantic Waters. Weather-wise, variable
conditions will prevail in response to the frequent pockets of
moisture reaching the islands and a shortwave trough at the upper
levels.

&&

.SHORT TERM...Today through Thursday...

An easterly perturbation will cross the islands today, shifting the
winds from the northeast. The most recent satellite imagery does not
show a significant increase in moisture content, but it should be
enough to increase the frequency of showers across the islands. At
the upper levels, the axis of a trough is crossing the Dominican
Republic, with the area of favorable dynamics over the local
islands. As the surface feature crosses the area, low level
convergence will combine with local effects and upper level support
to generate showers along the Cordillera Central and southwestern
Puerto Rico. On the other hand, the steering flow is still enhanced,
at 15 to 18 knots at the low levels, so showers should continue to
move quickly and accumulations should be limited. Nevertheless,
ponding of water can be expected on roads and low-lying areas.

On Wednesday, the trough will linger across the northeastern
Caribbean, while a low to mid level high will exit the eastern coast
of the United States. The surface high will once again tighten the
gradient, resulting in breezy conditions. These enhanced winds will
drag weak patches of moisture across the region, so a seasonal
pattern with passing showers will persist. Since the upper level
trough is maintaining instability aloft, one or two isolated
thunderstorms cannot be ruled out, especially across the local
waters. A similar pattern will persist on Thursday, with strong
breezes and irregular intervals of showers reaching the local
islands.

&&

.LONG TERM...Friday trough Tuesday...

Recent model guidances suggest a slightly drier trend for the long-
term period. On Friday, several patches of moisture embedded in
the trade winds will cross the islands frequently, maintaining
decent values of PWat over the CWA. At the upper levels,
instability provided by a shortwave trough will maintain colder
temperatures at 500MB. This evolving pattern will increase the
potential for shower development. Still, it will be limited and
localized over the eastern sections due to the trade wind cap
generated by the mid-level ridge in place. Breezy conditions from
a tight pressure gradient will also interfere with the rainfall
accumulation, limiting the flood threat over the islands.

A change in the dynamics at the upper levels will materialize on
Saturday as the shortwave trough moves eastward, leaving space
for stable conditions aloft. Considering the unfavorable
conditions for vertical development, the weather pattern from
Saturday onwards will be dominated by the passage of a few patches
of moisture embedded in the wind flows across the region.
Slightly warmer temperatures and more pockets of moisture are
forecasted for Monday onwards as the surface high pressure moves
into the eastern Caribbean, resulting in a more east-southeast
wind pattern.

&&

.AVIATION...
Mainly VFR conditions expected to prevail through the forecast
period. SHRA are moving across the local waters, reaching the USVI
and TJSJ terminals are times, but impacts to operations should be
brief. Additional activity is expected to develop after 17Z across
the Cordillera Central, with mountain obscuration. Winds are on the
strong side, coming out of the ENE at 17 to 22 knots, with stronger
gusts.

&&

.MARINE...

Combined seas will persist for most of the period. Today, fresh
to locally strong easterly winds and a northerly swell will
maintain hazardous marine and coastal conditions, where several
small craft advisories are in effect. A short improvement will be
noticed on Wednesday; however, another strong, northerly swell
pulse will invade the local waters late Thursday, increasing the
wave high up to 10 feet across the Atlantic and 5 to 7 feet for
most other waters. Winds will remain at up to 20 kts with higher
gusts.

Hazardous and life-threatening surf zone conditions continue
through tomorrow for the north and east-oriented beaches of
Puerto Rico (breaking waves of up to 12 feet), Culebra (breaking
waves of up to 11 feet), and the northern USVI (breaking waves of
up to around 10 feet tomorrow), where a High Surf Advisory is in
effect due to these dangerous breaking waves, hazardous swimming
conditions and localized beach erosion. A high risk of rip
currents will also be in effect for the north and east-oriented
beaches of Puerto Rico, Culebra, the northern USVI, and Vieques.
For more detailed information, please refer to the Coastal Hazard
Message product.

&&

.SJU WATCHES/WARNINGS/ADVISORIES...
PR...High Rip Current Risk through late Wednesday night for PRZ001-
002-005-008-012.

High Surf Advisory until 6 PM AST this evening for PRZ001-002-
005-008-012.

High Rip Current Risk through late tonight for PRZ010-013.

VI...High Surf Advisory until 6 PM AST this evening for VIZ001.

High Rip Current Risk through late tonight for VIZ001.

AM...Small Craft Advisory until 8 AM AST Thursday for AMZ710-741.

Small Craft Advisory until 8 AM AST this morning for AMZ712-715.

&&

$$

SHORT TERM & AVIATION...ERG
LONG TERM....LIS
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Re: Caribbean - Central America Weather

#21089 Postby cycloneye » Wed Feb 08, 2023 5:12 am

Area Forecast Discussion
National Weather Service San Juan PR
424 AM AST Wed Feb 8 2023


.SYNOPSIS...
Hazardous marine and coastal conditions will persist today and
will deteriorate even more tonight with the arrival of a second
pulse of a northerly swell. A variable weather pattern will
prevail for the rest of the workweek with frequent passing showers
and breezy conditions.


&&

.SHORT TERM...Today through Friday...

A surface high pressure centered north of the Bahamas will maintain
a strong trade wind flow out of the northeast. The low level
steering flow is expected to be around 20 knots today, and even
stronger on Thursday and Friday. The most recent satellite imagery
shows an area of enhanced moisture just north of the Virgin Islands.
Under a northeast flow, this feature will bring passing showers this
morning across the eastern municipalities of Puerto Rico and across
the U.S. Virgin Islands. Since the wind flow is strong, the showers
are expected to move fast without leaving high rainfall
accumulations, but wet roads and ponding of water on low-lying areas
can be anticipated this morning. Some showers may also develop over
southwestern Puerto Rico this afternoon, but the winds should move
them quickly across the Mona Channel.

On Thursday and Friday, the columnar moisture is expected to
decrease as a mid-level ridge promotes a drier air mass above 850
mb. However, induced patches of moisture will continue to reach the
islands irregularly, bringing additional showers for the same areas,
which is a typical pattern for this time of year. Once again,
significant flooding is not expected to occur with this activity,
but the users across eastern Puerto Rico and over the USVI can
anticipated this on and off showery pattern to continue through the
end of the workweek.
&&

.LONG TERM...Saturday trough Wednesday...

A variable weather pattern will persist for the long-period across
all the islands. At the surface, the pattern will be dominated by
the Atlantic high pressure generating breezy easterly winds. As
usual, the wind pattern will push patches of shallow tropical
moisture from time to time. According to the latest model
guidance, Saturday and Sunday appear to be the wettest days, with
PWat values up to 1.58 inches, according to the GFS global model.
Regardless of the Pwat values, a mid-level ridge promoting a
trade wind cap could limit the lifetime of the showers. Unsettled
conditions could result, however,from the presence of a strong
jet and the "zonal flow" of a shortwave trough at the upper levels.
These upper level conditions will induce colder temperatures at
500 MB, decreasing around -9 degrees. Given the expected
conditions, on Saturday into Sunday, expect frequent showers in
the morning over the east and the U.S. Virgin Islands, slightly
stronger over the west in the afternoon. There is a marginal risk
for thunderstorms with the heaviest activity; however, it will
all depend on the amount of moisture moving through the region.

From Monday onward, a frontal boundary moving out of the eastern
seaboard of the United States will induce a more southeasterly
wind flow over the region. Just like in previous days, patches of
moisture will reach the area at times, turning the skies cloudy
with passing showers. Additionally, the south component of the
wind will induce slightly warmer temperatures reaching the mid to
upper 80s in the coastal regions.

&&

.AVIATION...
Mainly VFR conditions expected to prevail through the forecast area.
SHRA will continue across the local waters, and could reach the USVI
terminals and TJSJ at times. Additional SHRA are expected across the
Cordillera Central after 17Z, causing mountain obscuration. Breezy
conditions will persist, with winds out of the NE at 18-22 kts, with
stronger gusts.

&&

.MARINE...
Hazardous marine and coastal conditions will prevail for the next
several days, mainly due to the combination of fresh to locally
strong easterly winds and a northerly swell, maintaining seas up
to 7 feet today, with winds up to 20 knots. Elsewhere, seas will
remain up to 6 feet, where small craft should exercise caution.
Another pulse of a north swell will invade the local region later
tonight into tomorrow, building seas up to 10-12 feet.

Hazardous surf zone conditions will continue for the north and
east-oriented beaches of Puerto Rico and the northern USVI, where
a high risk of rip currents is in effect. For tomorrow, the second
pulse of the northerly swell will create hazardous and life-
threatening coastal conditions again, with large breaking waves
nearly 14 feet across the north coast. For more detailed
information, please refer to the Coastal Hazard Message product.

&&

.SJU WATCHES/WARNINGS/ADVISORIES...
PR...High Rip Current Risk through Friday afternoon for PRZ001-002-
005-008-012.

High Rip Current Risk from Thursday morning through Friday
afternoon for PRZ010.

High Rip Current Risk until 6 AM AST early this morning for
PRZ013.

VI...High Rip Current Risk through Friday afternoon for VIZ001.

AM...Small Craft Advisory until 8 PM AST Friday for AMZ710-741.

Small Craft Advisory from 2 AM Thursday to 8 PM AST Friday for
AMZ712-715-722-732-742.

&&

$$

SHORT TERM...ERG
LONG TERM....LIS
AVIATION...ERG
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Re: Caribbean - Central America Weather

#21090 Postby cycloneye » Thu Feb 09, 2023 5:07 am

Area Forecast Discussion
National Weather Service San Juan PR
438 AM AST Thu Feb 9 2023

...New SYNOPSIS, AVIATION, MARINE, FIRE WEATHER...

.SYNOPSIS...Today's main hazards are marine conditions and rip
currents caused by increased winds and northerly swells. As a
result, Small Craft Advisories, Coastal Flood Advisories, High
Surf Advisories, and High Rip Current Risk are currently in
effect. Beachgoers and small craft should remain alert for
hazardous and life-threatening conditions. A variable weather
pattern will persist, influenced by intermittent patches of
shallow moisture and drier air steered in the general wind flow.
Moderate to locally heavy rains from more frequent passing showers
and afternoon convective development across western sections of
the islands could lead to limited excessive rainfall hazard
impacts.

&&

.SHORT TERM...Today through Saturday...

Breezy conditions persist across the northeastern Caribbean due to a
surface high pressure centered west of the southeastern United
States coastline. The high will maintain surface winds out of the
northeast today, then shifting more from the east on Friday and
Saturday, at speeds of 20 to 25 mph. This high stretches into the
mid-levels, maintaining dry air at these levels. At the upper
levels, a trough will be centered just east of the Virgin Islands,
with the best dynamics for showers development over the Leeward
Islands. Additionally, there is a frontal boundary north of the
Greater Antilles, but this feature should remain north of the area.
Through early in the weekend, the strong trade winds will carry
patches of moisture across the region, causing periods of passing
showers mainly across the eastern and northern municipalities of
Puerto Rico and across the United States Virgin Islands. These
patches of moisture are expected to be shallow, but occasionally
making it into the 700 mb level. As a result, rainfall accumulations
are not expected to be enough to cause significant flooding, but
roads are expected to be wet with ponding of water on areas of poor
drainage or with low elevation.

&&

.LONG TERM...Sunday through Thursday...

Model guidance suggests a variable weather pattern persisting
throughout the long-term forecast period, dominated by a surface
high pressure over the north Atlantic promoting moderate to
locally fresh easterly winds. Some variations of the general wind
flow are likely as the high drifts further eastward, and a frontal
boundary settles north of the region by the end of the period.
The expected breezy conditions will steer intermittent patches of
shallow moisture and drier air across the northeastern Caribbean,
causing significant variations in precipitable water levels
ranging from around 1.6 inches by Monday afternoon to 0.90 inches
by Wednesday afternoon. Despite these variations, a set of mid-
level ridges will maintain hostile conditions for deep convective
development with a marked trade wind cap inversion. However, an
upper-level shortwave trough, although gradually rising, will keep
500 mbar temperatures below seasonal climatological levels, and
thus, thunderstorm development is possible early in the period.

Overall, expect an increased frequency in trade wind shower
activity affecting windward sections of the islands during high
moisture periods, particularly by Sunday into early next week,
when precipitable water will remain at seasonal normal to above-
normal levels. Elsewhere, trade wind showers pushed further inland
by the strong steering flow and afternoon convective development
may bring periods of moderate to locally heavy rains. Yet, hazard
impact risks from excessive rainfall should remain at limited or
lower threat levels. If any impacts occur, they will result from
the ponding of water on roadways and poorly drained areas.
Seasonal temperatures will continue, ranging from the lower to mid
80 during the day across lower elevations to the lower to mid 50s
at nighttime across higher elevations.

&&

.AVIATION...Mainly VFR conditions expected to prevail through the
forecast period. SHRA will continue to move across the Caribbean
and Atlantic waters, occasionally reaching the USVI and TJSJ
terminals. Brief periods of reduced VIS and low ceilings are
possible. Winds will pick up after 13Z, coming out of the ENE at
18 to 26 knots at FL050.

&&

.MARINE...Fresh to locally strong trade winds and northerly
swells will maintain choppy to hazardous seas across the regional
waters throughout the week. Except for southwestern and southern
Puerto Rico coastal waters, Small Craft Advisories remain in
effect for the remaining local waters, with building seas up to 10
feet and occasionally higher.

Across the surf zone, a Coastal Flood Advisory is in effect for
most of the Atlantic coastline of Puerto Rico (breaking waves from
14 to 18 feet), Culebra, and the northern USVI (breaking waves
from 10 to 14 feet). A High Surf Advisory is also in effect for
these areas and beaches of western Puerto Rico (breaking waves up
to 12 feet). A High Risk of Rip Currents remains in effect for all
areas previously mentioned, as well as the beaches of St. Croix,
southwestern Puerto Rico, and Vieques. Under these conditions,
flooding of lots, parks, and roads with only isolated road
closures, dangerous swimming conditions, and localized beach
erosion is likely.

Stay tuned to the latest Coastal Hazard Forecast (CFWSJU) and Surf
Zone Forecast (SRFSJU) issued by WFO San Juan PR for further
information.

&&

.FIRE WEATHER...The lack of significant wetting rains has
supported additional soil and fuel deterioration across
southeastern Puerto Rico, where the most recent KBDI and 10-hour
fuel moisture indices reached 635 and 8 percent, respectively, in
Camp Santiago. Breezy to windy conditions will continue today, at
even slightly higher velocities than yesterday, with winds
forecast to peak around 18-22 mph with gusts up to around 25-30
mph between the late morning and early afternoon hours. Meanwhile,
a drier air patch steered under east-northeasterly winds, with
satellite-estimated precipitable water values of around an inch,
is expected to reach the local islands early this afternoon and
will likely cause relative humidity to fall below fire danger
thresholds of 45 percent. For this reason, a Fire Danger
Discussion for elevated fire weather conditions was issued, with
the highest impact across the southeastern coastal plains of
Puerto Rico.

&&

.SJU WATCHES/WARNINGS/ADVISORIES...
PR...High Rip Current Risk through Saturday afternoon for PRZ001-002-
005-008-012.

Coastal Flood Advisory until 6 PM AST Friday for PRZ001-002-005-
008-012.

High Surf Advisory until 6 AM AST Saturday for PRZ001-002-005-
008-010-012.

High Rip Current Risk through Saturday afternoon for PRZ010-011-
013.

High Surf Advisory from 6 PM this evening to 6 AM AST Saturday
for PRZ013.

VI...High Rip Current Risk through Saturday afternoon for VIZ001.

Coastal Flood Advisory until 6 PM AST Friday for VIZ001.

High Surf Advisory until 6 AM AST Saturday for VIZ001.

High Rip Current Risk through Saturday afternoon for VIZ002.

AM...Small Craft Advisory until 8 AM AST Sunday for AMZ710-712-715-
722-732-741-742.

Small Craft Advisory from 8 AM this morning to 8 AM AST Sunday
for AMZ725.

&&

$$

SHORT TERM/AVIATION...ERG
LONG TERM...ICP
PUBLIC...ERG/ICP
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Re: Caribbean - Central America Weather

#21091 Postby cycloneye » Fri Feb 10, 2023 5:09 am

Area Forecast Discussion
National Weather Service San Juan PR
420 AM AST Fri Feb 10 2023

.SYNOPSIS...Today's main hazards are marine conditions and rip
currents caused by fresh to strong winds and a northerly swell,
with Small Craft Advisories, Coastal Flood Advisories, High Surf
Advisories, and High Rip Current Risk in effect. Beachgoers and
small craft should remain alert for hazardous and life-threatening
conditions. A variable weather pattern will persist, influenced
by intermittent patches of shallow moisture and drier air steered
in the general easterly wind flow. Moderate to locally heavy rains
from more frequent passing showers and afternoon convective
development could lead to limited excessive rainfall hazard
impacts.

&&

.SHORT TERM...Today through Sunday...

Strong surface high pressure ridge anchored across the Atlantic
north of the region will maintain a fairly strong east northeast
wind flow through early Sunday; then becoming more east southeast by
Sunday afternoon as the ridge relocates into the central Atlantic,
and a cold front exits the eastern seaboard of the U.S. and enters
the west Atlantic. The upper trough sagging southwestward just north
and west of the region will lift farther northeast through
Saturday,while a weak mid to upper ridge replaces it. Another short
wave trough will however sweep across the region late Saturday into
Sunday to again destabilize the upper levels and result in increased
chance and frequency of passing shower activity through most of the
weekend. Afternoon shower development will be possible mainly on the
west-end and downwind of the the USVI, as well as over the central
interior and west sections of PR each day.

Main Impacts for the period are as follows:
-Windy to breezy east northeast wind conditions through early
Sunday, diminishing but still breezy especially along the coastal
areas by Sunday afternoon as winds become more southeasterly.
-The proximity of the upper trough and the brisk northeasterlies
will enhance the tradewind showers and bring periods of locally
heavy rains and brief gusty winds. This may lead to ponding of water
on roads and in poor drainage area. However, less frequent passing
clouds and shower activity is expected by Sunday as winds become
more east southeast and the local surface pressure gradient relaxes.
-Rough to choppy seas and hazardous marine conditions will persist,
with dangerous surf zone conditions forecast to continue into the
the upcoming weekend, due to northerly swell action and fresh to
locally strong east northeast winds. In addition, dangerous breaking
waves between 10-18 feet will remain possible, resulting in life-
threatening rip currents, minor coastal flooding, and beach erosion.

Small craft advisories and precautionary statement will remain in
effect for the local waters and passages. A coastal Flood watch is
in effect until 6 PM AST today. High surf advisory will remain in
effect until 6 AM AST saturday. High rip current will continue for
most of the local beaches through the period. Please refer to the
latest Coastal Waters Forecast (CWFSJU), Marine Weather Message
(MWWSJU) as well as the Coastal Hazard message (CFWSJU) and Surf
Zone Forecast (SRFSJU) issued by WFO San Juan PR.

&&

.LONG TERM...Monday through Friday...

Based on the most recent model guidance, the expected weather
conditions should remain variable throughout the forecast period,
influenced by an eastward-moving surface high pressure over the
north Atlantic, a frontal boundary to the north, and mid-level
ridging. Some variations in the general wind flow are likely as
the surface high drifts farther eastward, and a frontal boundary
settles north of the region by the end of the period, but winds
should generally remain easterly at 10-20 mph. The expected breezy
conditions will steer intermittent patches of shallow moisture
and drier air across the northeastern Caribbean through Thursday,
with 24-36 hour periodical moisture variations from around 0.9-1.1
inches during the driest periods to 1.3-1.4 inches during the
wettest periods. Following model guidance, the remnants of the
aforementioned frontal boundary should reach the local islands
late Thursday night into Friday, causing precipitable water values
to peak slightly higher at around 1.5 inches. Despite these
variations, hostile conditions for deep convective development
with a marked trade wind cap inversion should limit showers, and
thus, rainfall accumulations.

Overall, expect variable weather conditions with an increased
frequency in trade wind shower activity and possible afternoon
convective development during high moisture periods, particularly
on Tuesday, Wednesday, and Friday, when above-normal seasonal
precipitable water values are likely. So far, the highest impact
will focus on windward sections of the islands, but trade wind
showers pushed further inland by the strong steering flow and
afternoon convective development may bring periods of moderate to
locally heavy rains to other areas. Yet, hazard impact risks from
excessive rainfall should remain at limited threat levels at most,
with ponding of water on roadways and poorly drained areas
possible. Seasonal temperatures will continue, ranging from the
lower to mid 80 during the day across lower elevations to the
lower to mid 50s at nighttime across higher elevations.

&&

.AVIATION...Mainly VFR conds to prevail through fcst prd. SHRA
will continue to move across the Caribbean and Atlantic waters,
occasionally reaching the USVI and TJSJ terminals. Brief periods
of MVFR reduced VIS and low ceilings psbl due to SHRA with Mtn Top
obscr over E interior of PR til at least 10/13Z. SFC wnd aft
10/13Z bcmg ENE 15-20 kts with hir gusts psbl btw 25-30 kts...then
diminishing to around 10 kts aft 10/22Z. Strong L/LVL winds fm
ENE btw 20-30 kts BLO FL140. Maximum winds W-NW 40-50 kts btwn
FL320-370.

&&

.MARINE...Fresh to locally strong trade winds and northerly swells
will maintain choppy to hazardous seas across the regional
waters. Except for southwestern and southern Puerto Rico coastal
waters, Small Craft Advisories remain in effect, with building
seas up to 12 feet and occasionally higher.

Across the surf zone, a Coastal Flood Advisory also remains in
effect for most of the Atlantic coastline of Puerto Rico (breaking
waves from 14 to 18 feet), Culebra, and the northern USVI
(breaking waves from 10 to 14 feet). A High Surf Advisory is also
in effect for these areas and beaches of western Puerto Rico
(breaking waves up to 12 feet). A High Risk of Rip Currents
remains in effect for all areas previously mentioned, as well as
the beaches of St. Croix, southwestern and southeastern Puerto
Rico, and Vieques. Under these conditions, flooding of lots,
parks, and roads with only isolated road closures, dangerous
swimming conditions, and localized beach erosion is likely.

&&

.SJU WATCHES/WARNINGS/ADVISORIES...
PR...Coastal Flood Advisory until 6 AM AST Saturday for PRZ001-002-
005-008-012.

High Rip Current Risk through Saturday afternoon for PRZ001-002-
005-008-010-012-013.

High Surf Advisory until 6 AM AST Saturday for PRZ001-002-005-
008-010-012-013.

High Rip Current Risk through late tonight for PRZ003-011.

VI...Coastal Flood Advisory until 6 AM AST Saturday for VIZ001.

High Rip Current Risk through Saturday afternoon for VIZ001-002.

High Surf Advisory until 6 AM AST Saturday for VIZ001.

AM...Small Craft Advisory until 8 AM AST Sunday for AMZ710-712-715-
722-725-732-741.

Small Craft Advisory until 8 AM AST Saturday for AMZ742.

Small Craft Advisory until 2 PM AST this afternoon for AMZ745.

&&

$$

SHORT TERM...RAM
LONG TERM....ICP
AVIATION...RAM
PUBLIC...ICP
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Re: Caribbean - Central America Weather

#21092 Postby cycloneye » Sat Feb 11, 2023 5:28 am

Area Forecast Discussion
National Weather Service San Juan PR
507 AM AST Sat Feb 11 2023

.SYNOPSIS...Hazardous marine and coastal conditions continue. The
High Surf Advisory will be in effect for Culebra, St. Thomas & St.
John and the Atlantic Coastline of Puerto Rico until 6 PM AST.
Nevertheless, the high risk of life-threatening rip currents will
continue. Trade wind showers will move inland under breezy winds
towards sectors of the local islands, otherwise generally fair
weather should prevail. Afternoon shower development should be
limited and focused on western PR and downwind of St. Croix.

&&

.SHORT TERM...Today through Monday...

Strong surface high pressure ridge will continue to shift farther
east into the north Central Atlantic by Sunday, allowing the local
pressure gradient to gradually relax and become more east southeast
by Sunday afternoon. Winds are also forecast to continue to diminish
Sunday through Monday as an induced surface trough sets up just west
of the region, in response to a cold front which is forecast to
enter and cross the west and southwest Atlantic. A weak upper level
ridge will gradually erode today through Sunday, as a short wave
trough is forecast to cross the region and again destabilize the
upper levels, resulting in the increased chance and frequency of
passing trade wind shower development for the rest of the weekend.
Afternoon shower development will be possible but mainly limited to
the west-end and downwind of the the USVI, as well as over portions
of the east interior and west to northwest sections of PR each day.
However, no significant accumulations are anticipated at this time.

Main Impacts for the period are as follows:
-Breezy east northeast wind becoming more easterly later today into
early Sunday, then diminishing but still breezy especially along the
coastal areas by Sunday afternoon, as the winds become more
southeasterly into Monday.
-The proximity of an approaching short wave trough and moderate
easterlies will enhance the tradewind showers and bring periods of
locally heavy rains and brief gusty winds across the coastal waters
and mainly portions of the north and east coastal areas during the
rest of the morning hours. This will be followed by some afternoon
shower development over parts of the interior and west to northwest
sections of Puerto Rico, and mainly downwind of the USVI through
Sunday. Some of the heaviest rains may may lead to ponding of water
on roads and in poor drainage area. Less frequent passing clouds and
trade wind showers is so far forecast by Monday with the afternoon
shower activity focused more in the northwest sections of Puerto
Rico, as winds become more southeasterly.
-Choppy seas and hazardous marine conditions will continue through
the weekend, with dangerous surf zone conditions forecast to
continue due to the combination of a slowly fading northerly swell
action and fresh to locally strong easterly winds. Dangerous
breaking waves between 10-16 feet will remain possible until later
today, diminishing to 6-8 feet by Sunday and Monday. Therefore life-
threatening rip currents, minor coastal flooding, and beach erosion
will remain possible at least the rest of today into early Sunday. A
gradual improvement is expected by Monday.

Small craft advisories and precautionary statement will remain in
effect for the local waters and passages. A High surf advisory will
remain in effect until 6 PM AST today. High rip current will
continue for most of the local beaches at least until early Sunday
then becoming a moderate risk for most beaches by Monday except
for the northwest to north central beaches of Puerto Rico and
Culebra which will remain at a high risk for the rest of the
weekend. Please refer to the latest Coastal Waters Forecast
(CWFSJU), Marine Weather Message (MWWSJU) as well as the Coastal
Hazard message (CFWSJU) and Surf Zone Forecast (SRFSJU) issued by
WFO San Juan PR.

&&

.LONG TERM...Tuesday through Saturday...

Variable weather conditions are expected for the long term forecast
period. High temperatures will range from the low to mid 80s over
coastal areas. Low temperatures will range from the low to mid 50s
across higher elevations of Puerto Rico, and around the mid 70s
across higher elevations of the local islands. Patchy fog is also
expected during the overnight to early morning hours across areas of
the interior of Puerto Rico. At surface level, by Tuesday, a high
pressure system over the central Atlantic, a low pressure system,
and associated frontal boundary, over the central Atlantic, and a
high pressure system moving over the western Atlantic will influence
the region. Winds should gradually back to the east northeast to
start the forecast period and generally remain from that direction
through the week. Breezy conditions should also persist,
particularly by midweek onward, these wind will move patches of
humid air as well as patches of dry air over our region. Model
guidance indicates precipitable water (PWAT) values of around 1.3 to
1.4 inches with the more humid patches and PWAT values of below or
near an inch in the drier patches. A notable peak in (PWAT) values
can be seen on Thursday night and into Friday due to moisture from
remnants of a frontal boundary reaching our region. Behind this
moisture, current model guidance suggest a dry pattern for Friday
morning through Saturday. Any available moisture will, however,
remain mostly below 700 mb, as a trade wind cap will be present due
to mid-level ridging affecting the region. This will serve to limit
any shower development. Nevertheless, passing shower activity will
advect towards windward sections of the islands from time to time.
Stronger showers may move further inland due to breezy conditions
and afternoon convection could also develop due to diurnal and local
effects. Stronger shower activity are more likely to occur when
patches of more humid air are affecting the region, these could
result in moderate to possibly locally heavy rains possibly
resulting in ponding of water over roadways and poorly drained
areas. Breezy conditions will also serve to limit accumulations as
showers will move faster over the area.

&&

.AVIATION...VFR at all terminals. Wdly SCT SHRA ovr the regional
waters and en route btw the local islands. FEW SHRA will reach
the north and east coastal areas from time to time with VCSH psbl
at TJSJ/TJBQ and USVI terminals til 11/13Z. Brief MVFR with
reduced VIS and low ceilings psbl due to SHRA with Mtn Top obscr
over E interior of PR til at least 11/13Z. SFC wnd fm E to NE less
than 10 kts bcmg fm ENE 15-20 kts with hir gusts btw 25-30 kts
aft 11/14Z. L/LVL wnd fm ENE 15-25 kts BLO FL200 bcmg fm W abv
with MAX wnd 65-70 kts btw FL280-FL320. no sig operational wx
impacts at local terminals attm.

&&

.MARINE...CARICOOS's San Juan Buoy recently showed wave heights
of around 7 feet. Choppy and hazardous marine conditions will
continue through the weekend due to a gradually fading northerly
swell and fresh to locally strong easterly winds. Small Craft
Advisories remain in effect for most local waters. Dangerous
coastal conditions continue, breaking waves between 10-16 feet
remain possible until late in the afternoon, before diminishing to
6-8 feet. Because of this a High Surf Advisory will be in effect
until 6 PM for the western to the northern to the eastern coasts
of Puerto Rico, as well as for Culebra and the USVI. A High Risk
of rip currents will continue for these beaches tonight, as well
as for Vieques and St. Croix until this evening. Life- threatening
rip currents, minor coastal flooding, and beach erosion will
remain possible at least the rest of today into early Sunday.

&&

.SJU WATCHES/WARNINGS/ADVISORIES...
PR...High Rip Current Risk through Sunday afternoon for PRZ001-010-
012.

High Surf Advisory until 6 PM AST this evening for PRZ001-002-
005-008-010-012.

High Rip Current Risk through late tonight for PRZ002.

High Rip Current Risk until 6 AM AST early this morning for
PRZ003-011.

High Rip Current Risk through late Sunday night for PRZ005-008.

High Rip Current Risk through this afternoon for PRZ013.

High Surf Advisory until 6 AM AST early this morning for PRZ013.

VI...High Surf Advisory until 6 PM AST this evening for VIZ001.

High Rip Current Risk through late tonight for VIZ001-002.

AM...Small Craft Advisory until 8 PM AST Sunday for AMZ710-722-732-
741.

Small Craft Advisory until 8 AM AST Sunday for AMZ712-715-725-
742.

&&

$$

SHORT TERM...RAM
LONG TERM....MRR
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Re: Caribbean - Central America Weather

#21093 Postby cycloneye » Sun Feb 12, 2023 6:16 am

Area Forecast Discussion
National Weather Service San Juan PR
430 AM AST Sun Feb 12 2023

.SYNOPSIS...Mainly fair weather conditions should prevail, with
the exception of some passing showers pushing inland from time to
time. Some afternoon shower development is also possible over
western Puerto Rico. However, any activity will be limited and
rainfall accumulations will be minimal. Choppy seas will continue
due to a fading northerly swell and moderate to fresh easterly
winds. Conditions will continue to gradually improve by the start
of the workweek as seas subside. A High Risk of Rip Currents is in
effect for the northwest to northeast beaches of Puerto Rico, as
well as the beaches of Culebra and the northern USVI.

&&

.SHORT TERM...Today through Tuesday...

A broad upper level trough is forecast to linger across the region
through Monday to aid in destabilizing the upper levels. This will
result in some enhancement of the trade wind showers especially
during the overnight and early morning hours. A mid to upper level
ridge will build and spread across the region from the west by
Tuesday resulting in stable conditions aloft. A dominant surface
high pressure ridge now spread across the central Atlantic will
slowly shift farther north and east into the north central Atlantic
through Monday. this will allow the local pressure gradient to relax
and the easterly winds to become more southeasterly by Monday and
Tuesday. Winds are still forecast to continue to diminish through
the period as an weakly induced surface trough sets up just west of
the region, in response to a cold front which will enter and cross
the west and southwest Atlantic promoting lighter local winds.
Afternoon shower development will remain possible each day but
should be limited to over portions of the east interior, and west to
northwest sections of Puerto Rico as well as on the west-end or just
downwind of the the USVI. Significant rainfall is not expected
during most of the period, as model guidance suggests limited
moisture advection with precipitable waters values to be below
normal and range between 0.75-1.20 inches today increasing to near
normal with more seasonal values by Monday and Tuesday ranging
between 1.25-1.30 inches.

Main Impacts for the period are as follows:
-Breezy conditions to continue by late morning into the afternoon
hours particularly along the coastal areas. Winds will become more
east southeast later today, then gradually diminishing and becoming
more southeasterly on Monday and Tuesday resulting in less frequent
trade wind moisture advection.
-The proximity of the lingering upper trough and prevailing low
level easterlies will enhance the tradewind showers and bring
periods of locally heavy rains and brief gusty winds across the
coastal waters and mainly portions of the east coastal areas during
the rest of the morning hours. This will be followed by limited
afternoon shower development over parts of the interior and west to
northwest sections of Puerto Rico, and mainly downwind of the USVI
through Sunday. Some of the heaviest rains may lead to ponding of
water on roads and in poor drainage area. The advective pattern of
passing clouds and trade wind showers is forecast to be less
frequent today as a slot of drier air will cross the region. Passing
shower activity will however increase once again early Monday and
Tuesday as the aforementioned weakly induced surface trough develops
and crosses the region. By then afternoon shower activity will be
focused more in the northwest sections of Puerto Rico.
-Choppy seas marine conditions will continue through the period but
with gradually subsiding seas, as the northerly swell as well as the
local winds continue to fade and diminish respectively. Moderate to
fresh easterly winds will prevail today becoming more southeasterly
on Monday and Tuesday. Small craft advisories and precautionary
statement will remain in effect for the local waters and passages.
Life-threatening rip currents will remain likely for the northwest
through Northeast facing beaches of Puerto rico and Culebra and the
northern U.S. Virgin Islands today, and also possible for the
remaining beaches including those of St Croix during the period.

&&

.LONG TERM...Wednesday through Sunday...

Long term forecast remains mostly on track with variable weather
conditions expected for this period. At surface level, a high
pressure system moving over the western Atlantic will continue
spreading eastward during the long term period, influencing the
region. Winds should generally be breezy and from the east northeast
through Sunday. These winds will move patches of moisture and
patches of drier air over the local islands during the period. Model
guidance continues to indicate precipitable water (PWAT) values of
around 1.3 to 1.4 inches with the more humid patches and PWAT values
of below or near an inch with the drier patches. More humid PWAT
values can be seen on Thursday night and into Friday due to moisture
from remnants of a frontal boundary reaching our region. Behind this
moisture, current model guidance suggest a dry pattern for Friday
morning through the weekend. Available moisture will remain mostly
below 700 mb (even mostly below 800 mb during the weekend), as a
trade wind cap will be present due to mid-level ridging affecting
the region. This will serve to limit any shower development. Breezy
conditions will also serve to limit accumulations. Passing shower
activity will advect towards windward sections of the islands from
time to time. Stronger showers may move further inland due to breezy
conditions and afternoon convection could also develop due to
diurnal and local effects. Stronger shower activity are more likely
to occur when patches of more humid air are affecting the region,
these could result in moderate to possibly locally heavy rains
possibly resulting in ponding of water over roadways and poorly
drained areas. High temperatures over coastal areas will range from
the low to mid 80s. Low temperatures, on the other hand, will range
from the low to mid 50s across higher elevations of Puerto Rico, and
around the mid 70s across higher elevations of the local islands.
Patchy fog is also expected during the overnight to early morning
hours across sectors of interior Puerto Rico.

&&

.AVIATION...VFR at all terminals. Mstly isold SHRA ovr the regional
waters and en route btw the islands. Ocnl patches of low cld lyrs
nr FL025... FL050 with FEW SHRA brushing the windward side of the
islands from time to time with VCSH psbl at TJSJ and USVI
terminals til 12/13Z. Brief MVFR psbl due to low clds and SHRA
with Mtn Top obscr over the E interior of PR til 12/13Z. SFC wnd
lgt/vrb with land breeze variations, bcmg fm E increasing to
around 15 kts with ocnly hir gusts and sea breeze variations aft
12/14Z. L/LVL wnd fm E 15-20 kts BLO FL200 bcmg fm W abv with MAX
wnd 60-65 kts btw FL280-FL320. No sig operational wx impacts at
local terminals attm.

&&

.MARINE...Choppy seas will continue due to a fading northerly
swell and moderate to fresh easterly winds. Conditions will
continue to gradually improve by the start of the workweek as seas
subside. Small Craft Advisories continue to be in effect for the
offshore waters and local passages due to seas of up to 7 feet.
Small Craft Should Exercise Caution over most other local waters.
A High Risk of Rip Currents remains today (from 6 AM AST) for the
northwest to northeast beaches of Puerto Rico, as well as the
beaches of Culebra and the northern USVI.

&&

.SJU WATCHES/WARNINGS/ADVISORIES...
PR...High Rip Current Risk through late tonight for PRZ001-005-008.

High Rip Current Risk through this afternoon for PRZ002-010-012.

High Rip Current Risk until 6 AM AST early this morning for
PRZ013.

VI...High Rip Current Risk through this afternoon for VIZ001.

High Rip Current Risk until 6 AM AST early this morning for
VIZ002.

AM...Small Craft Advisory until 8 AM AST Monday for AMZ710-741.

Small Craft Advisory until 8 PM AST this evening for AMZ722-732.

&&

$$

SHORT TERM...RAM
LONG TERM....MRR
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Re: Caribbean - Central America Weather

#21094 Postby cycloneye » Mon Feb 13, 2023 4:51 am

Area Forecast Discussion
National Weather Service San Juan PR
502 AM AST Mon Feb 13 2023


.SYNOPSIS...
Intervals of a drier airmass and occasional patches of low level
moisture will continue to cross the region under a light southeast
winds today, as a weak induced surface trough sets up over region
and a cold front crosses the west Atlantic. Winds are forecast to
become northeasterly and increase by Wednesday as a high pressure
ridge builds over the west Atlantic and the cold front sinks southwards
across the region Wednesday through Thursday. This will increase moisture
convergence and potential for enhanced shower development along with
breezy to windy conditions expected by then, along with deteriorating
seas for the latter part of the work week. A gradual improvement in
marine and surf zone conditions is far forecast for the early part
of the work week, followed by deteriorating conditions hereafter.

&&

.SHORT TERM...Today through Wednesday...

At surface level, a high pressure system over the central Atlantic
will continue moving eastward, followed by a frontal low moving
northeast across the Atlantic. Another surface high pressure system
that will start to reach the western Atlantic by Tuesday and
continue spreading eastward. These, along with a weak surface
trough, will influence the region, and promote winds to become more
southeasterly today. By late afternoon Tuesday, winds should
gradually back to become more easterly and then more northeasterly
by Wednesday while also increasing, promoting breezy conditions.
Southeast winds today will promote higher temperatures across the
islands. Intervals of humid and drier air masses will move toward
the is lands through mid week. Both satellite derived precipitable
water (PWAT) and doppler radar indicate moist air along with
embedded showers moving across the area. A small patch of dry air
should also affect the area during the morning hours before another
moist air mass crosses, mostly through Tuesday night. Another dry
air mass will reach the region Thursday night and into Wednesday
morning. As the winds turn more northeasterly, as more moisture
remnants of a frontal boundary will move towards the local islands,
the bulk of the moisture should reach the islands to start the long
term forecast period. Mid level ridging will also affect the region,
this will serve to limit shower development. Any moisture that
reaches the area will be below around 700 mb, as dry air will
continue in the mid to upper levels. Nevertheless, passing shower
activity will continue to advect towards windward sections of the
islands today, while also moving across the local waters, promoting
generally showery conditions. Stronger showers are more likely to
occur when patches of more moist air are crossing the region,
possibly resulting in ponding of water over road and poorly
drained areas. Afternoon convection could also develop due to
diurnal and local effects, for today this activity could occur
mainly over northwest Puerto Rico.


&&

.LONG TERM...Thursday through Tuesday...
In the upper levels, a broad polar trough is forecast to cross
the west Atlantic on Thursday and become amplified across by
Friday then sagging south across the region by Saturday, with a
mid to upper level ridge expected to build in from the west
thereafter resulting in erosion of low level moisture and
diminishing instability aloft. Overall improving conditions with
more typical advective weather condition expected for the weekend.
Induced surface trough weakens by Thursday as a surface high
pressure ridge builds over the west Atlantic. The local pressure
gradient tightens and the northeast winds increase as a cold front
sinks southwards, across the local Atlantic and crosses the
islands by early Friday then making its way south of the islands
by Friday afternoon. Increasing winds will follow with brisk
northeast winds promoting breezy to windy conditions at least into
the early part of the weekend. An overall drier and stable
airmass is forecast by then but advective moisture transport will
increase resulting in more frequent of passing clouds and showers
especially during the overnight and early morning hours. This will
be followed by limited showers in the west and southwest Puerto
Rico and the rest of the islands including the USVI during the
afternoon hours thereafter.

Expected impacts are as follows:
Wettest day so far based on recent guidance is Thursday into Friday
conditions gradually improving by Saturday into the weekend but with
breezy conditions continuing thus promoting more frequent passing
early morning showers at least until Saturday. Winds relax late
Saturday and through the rest of the weekend with continuous passing
showers affecting the north and east coastal areas each day followed
by limited afternoon showers mainly over the interior and southwest
Puerto Rico.
-Ponding of water on roads and urban and small stream flooding
likely Thursday into Friday and possible through the weekend but in
isolated areas. Winds diminish over weekend but pick up and become
more northeasterly by monday and Tuesday with trade wind shower
activity to return bringing moisture fragments from old frontal
boundary.
-Choppy to rough and hazardous seas from Thursday onwards due to
the combination of a northerly swell and increasing east to north
east winds. Dangerous marine and surf zone condtions are therefore
forecast from Thursday through Friday with fading swell action by
the weekend, however choppy seas are however still forecast to
continue during the entire period.&&

.AVIATION...
Mainly VFR conditions are expected across all terminals. Passing
SHRA moving across TJSJ/TISX/TIST could promote briefly MVFR
conditions. Wind flow generally from the ESE at up to 15-20 kts
with higher gusts and sea breeze variations &&

.MARINE...
Small Craft Advisories and High Risk of Rip Currents statements
have been allowed to expire as a gradual improvement in seas and
surf zone conditions are expected today through at least Tuesday.
Seas will however remain choppy and life- threatening rip currents
with a moderate risk will remain possible. Marine and surf zone
conditions are expected to once again deteriorate by the latter
part of the work week. Stay tuned!

&&

.SJU WATCHES/WARNINGS/ADVISORIES...
PR...None.
VI...None.
AM...None.
&&

$$

SHORT TERM...MRR
LONG TERM....RAM
AVIATION...MRR
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Re: Caribbean - Central America Weather

#21095 Postby cycloneye » Tue Feb 14, 2023 5:03 am

Area Forecast Discussion
National Weather Service San Juan PR
352 AM AST Tue Feb 14 2023

.SYNOPSIS...An overall drier airmass is expected but occasional
patches of low level moisture will continue to cross the region
under a light east southeast winds today, as an induced surface
trough weakens over region and a cold front crosses into the west
central Atlantic. Winds will become northeasterly and increase by
Wednesday as a surface high pressure ridge builds over the west
Atlantic and the cold front sinks southwards across the region
through Thursday. This will increase moisture convergence and favor
potential for some enhanced shower development along with breezy to
windy conditions along with deteriorating seas and surf zone
conditions once again for the latter part of the work week.

&&

.SHORT TERM...Today through Thursday...
Weather conditions will be characterized by intervals of patches of
moisture and patches of dry air moving into the region. A surface
high pressure will start moving into the western Atlantic, while a
cold front crosses into the western central Atlantic. The high will
continue spreading eastward during the period. Winds will be east
southeast today, as an induced surface trough weakens over the area.
Winds will start backing to become more northeasterly by tonight,
into Wednesday and through the rest of the short term forecast
period. Winds will also increase by late Wednesday and into
Thursday, promoting breezy conditions. Any moisture that reaches the
area will be below around 700 mb, as dry air will continue in the
mid to upper levels. Overall fair weather conditions are expected
with only passing shower activity advecting towards windward sectors
of the islands and the local waters, especially each morning over
the eastern forecast area, promoting showery conditions. Stronger
showers are more likely to occur when patches of more moist air,
remnants of past frontal boundaries, are crossing the region,
possibly resulting in ponding of water over roadways and poorly
drained areas. Afternoon convection could also develop due to
diurnal and local effects, especially over areas of western Puerto
Rico. This afternoon convection can possibly occur over northwestern
Puerto Rico today, and southwestern Puerto Rico tomorrow and
Thursday with limited accumulations.

&&

.LONG TERM...Friday through Wednesday...
An upper trough will continue to become amplified across the northeast
Caribbean Friday through Saturday, as an upper ridge builds in from
the west across the islands. This will result in a continued erosion
of low level moisture with increasing stability aloft through the weekend.
Overall improving and mostly fair weather conditions are therefore expected,
with a more typical advective weather pattern expected. A surface high
pressure ridge will build over the west Atlantic while spreading southwards
across the region. This in turn will tighten the local pressure gradient
resulting in increasing northeast winds. Moisture remnants from a cold
front will sink southwards across the local Atlantic, while making its
way south of the islands by Friday afternoon. Brisk northeast low level
winds will promote breezy to windy conditions at least into early Saturday,
then gradually diminish the rest of the weekend, when winds are forecast
to become light to moderate from the east northeast. An overall drier
and stable airmass is forecast across the region during the latter
part of the period, but advective moisture transport will continue
resulting in intervals of passing clouds and showers each day, particularly
during the overnight and early morning hours. This will be followed
by limited afternoon showers in the west and southwest Puerto Rico
and the rest of the islands including the USVI.

Based on recent model guidance and the expected impacts are as follows:
- Wettest day still appears to be early Friday morning but with
gradually improving conditions by Friday afternoon into
Saturday. Breezy conditions will linger into Saturday thus
promoting more intervals of passing early morning showers. Winds
will continue to diminish late Saturday and through the rest of
the weekend. Less frequent passing showers are forecast to
affect the north and east coastal areas each day followed by
limited afternoon showers mainly over the interior and southwest
Puerto Rico.
- Minor ponding of water on roads will be possible with the brief
heavy rains, but no significant rainfall accumulations are
anticipated. Winds pick up and become more northeasterly through
Monday, then easterly the rest of the period, with fast moving
trade wind shower activity expected to return bringing moisture
fragments from old frontal boundary across the islands and
coastal waters from time to time.
- Choppy to rough and hazardous seas continuing on Friday and
through at least the early part of the period, due to the
combination of a northerly swell and increasing east to
northeast winds. Dangerous marine and surf zone condtions will
therefore be likely through Friday with fading swell action over
the weekend. However choppy wind driven seas are still forecast
to continue during the entire period. Small craft advisories and
life- threatening rip current risk statements will likely be
required.

&&

.AVIATION...
Mainly VFR conditions are expected again across all terminals.
Brief MVFR conditions could be experienced across TJSJ and USVI
terminals due to passing shower activity. Wind flow generally from
the ESE at up to 15 kts before backing to become more ENE by tonight,
winds will have higher gusts and sea breeze variations. Afternoon
VCSH possible mainly for TJBQ.

&&

.MARINE...
Recent data from the surrounding buoys continued to suggest
improving marine conditions with Seas subsiding to 4 feet or less
and diminishing east to southeast winds between 10 to 15 kts over
the offshore waters and passages, and 5 to 10 knots elsewhere.

Moderate risk of rip currents will persist for most north- and
east-facing beaches of the local islands.

&&

.SJU WATCHES/WARNINGS/ADVISORIES...
PR...None.
VI...None.
AM...None.
&&

$$

SHORT TERM...MRR
LONG TERM....RAM
AVIATION...MRR
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Re: Caribbean - Central America Weather

#21096 Postby cycloneye » Thu Feb 16, 2023 11:09 am

Area Forecast Discussion
National Weather Service San Juan PR
526 AM AST Thu Feb 16 2023

.SYNOPSIS...

Patchy moisture will continue to support passing shower activity
across the region for much of the foreseeable future. An old frontal
boundary is forecast to affect the region today into tomorrow, and
today will likely be the wettest day of the next several days.
Decreasing amounts of patchy moisture are expected during the next
week, resulting in a decrease in shower activity through much of the
work week.

Hazardous marine and coastal conditions are expected through at
least the end of the week. Seas of up to 10 feet are expected by
tonight for portions of the local waters, particularly the offshore
Atlantic waters. There is a high risk of rip currents for the vast
majority of north-facing beaches.

&&

.SHORT TERM...Thursday through Saturday...

High pressure of moderate strength at lower levels is in the western
Atlantic and will move slowly westward through the period. A cold
front will push off the eastern coast of the United States on Friday
and move southeast across the same waters Friday night and Saturday.
Low pressure near 24 north and 40 west will develop on Saturday in
response to a rapidly deepening low at mid and upper levels. At the
surface this low will deepen along a previous front and one that is
now along 20 north latitude north of the area. This front is already
spreading some moisture ahead of it and will cross through the area
tonight. Moisture is generally less than 8000 feet deep; will deepen
as the front crosses, and then become shallower as the air behind
the front passes through Friday and Saturday. This will bring the
northern half of Puerto Rico and the U.S. Virgin Islands more
frequent showers mainly tonight and Friday. Showers will slowly
taper off as we enter the weekend. Amounts could reach 2 inches in
the wettest areas, namely along the windward slopes of the local
mountains. Through it all Puerto Rico will experience fresh to strong
east northeast winds with gusts that could reach 35 mph near
showers. These conditions are expected to continue into the long
term period.

&&

.LONG TERM...Sunday through Friday...

Patchy moisture, largely the fragmented remnants of old frontal
boundaries, remains the main driver for conditions through the long-
term period. The wettest days look to be Sunday into Monday. Aloft,
there is some troughing at 500 hPa and aloft, associated with a low
to the northeast. This will linger nearby, with the trough axis
mostly to the south of the islands, into Monday. Despite some modest
support aloft, the dearth of moisture above around 800 to 700 hPa
will likely preclude much in the way of substantial convective
development. Still, the moisture should more than suffice to sustain
the passing shower activity.

Moisture decreases on Tuesday, remaining mostly below seasonal
normals. This will result in decreased shower activity. On
Wednesday, an old frontal boundary is expected to arrive; most of
the moisture with this boundary is forecast to only interact with
the islands briefly, during which time shower activity will increase
modestly. Moisture decreases again by Thursday. On Friday,
additional patches of moisture are forecast to arrive by the
morning. Because of this, Friday is likely to be the wettest day
after Monday.

Forecast confidence is at typical levels. The main source of
uncertainty lies in the timing, location, and strength of the
patches of moisture that are the fragmented remains of old frontal
boundaries. This will likely shift, but overall the trend is likely
to remain generally similar, with drier weather during the week, and
wetter conditions around the start and end of the week.

&&

.AVIATION...
(12Z TAFS)

Mainly VFR conditions are expected across the forecast area, with
brief MVFR CIGS and mtn topping possible. SHRA will increase aft
17/00Z with MVFR and mtn obscurations incrg thru 17/12Z. ENE winds
will continue at 12-20 kts 14-23Z and 8-15 kt 23- 14Z with hir
gust for at least the next 36 hrs. Max winds NW 30-35 kts btwn
FL400-430.

&&

.MARINE...

Winds continue out of the northeast at around 15 to 25 knots, with
gusts up to 35 knots. This is causing choppy conditions across the
waters. For the Atlantic waters, there is a swell that is
approaching the region. At this time, it appears likely that at
least for today, the wind wave and swell will have quite similar
contributions at times to the overall sea state. Seas of around 8 to
10 feet are expected by tonight for the offshore Atlantic waters.

There is a high risk of rip currents for north-facing beaches of
Puerto Rico, as well as beaches of the USVI and Culebra. This risk
will persist through the weekend.

&&

.SJU WATCHES/WARNINGS/ADVISORIES...
PR...High Rip Current Risk through Sunday afternoon for PRZ001-002-
005-008.

High Rip Current Risk through Sunday afternoon for PRZ010-012.

VI...High Rip Current Risk through Sunday afternoon for VIZ001-002.

AM...Small Craft Advisory until 2 PM AST Sunday for AMZ710-722.

Small Craft Advisory from 2 PM this afternoon to 2 PM AST Sunday
for AMZ712-715-725-732-741.

Small Craft Advisory from 8 PM this evening to 2 PM AST Sunday
for AMZ742.
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Re: Caribbean - Central America Weather

#21097 Postby cycloneye » Fri Feb 17, 2023 5:31 am

Area Forecast Discussion
National Weather Service San Juan PR
526 AM AST Fri Feb 17 2023


.SYNOPSIS...

Drier air has moved into the region from the northeast, resulting in
a decrease in passing shower activity. However, patchy moisture will
still help maintain some passing shower activity over the region.
Overall, a general trend towards decreasing shower activity is
expected into next week.

Fresh to strong winds are maintaining choppy conditions across the
waters, while a northerly swell continues to affect the local
Atlantic waters and passages. Confused seas are expected in areas
exposed to the north. Hazardous marine and coastal conditions are
expected to persist through the weekend.

&&

.SHORT TERM...Today through Sunday...

High pressure of moderate strength at lower levels is in the western
Atlantic and will move slowly westward through the period while
shrinking. A cold front will push off the eastern coast of the
United States late this afternoon and move southeast across the same
waters tonight through Sunday but is not expected to move much
farther south than 29 degrees north. Low pressure near 24 north and
40 west will develop on Saturday in response to a rapidly deepening
low at mid and upper levels. At the surface this low will deepen
along a previous front that just crossed through Puerto Rico and the
northern U.S. Virgin Islands. Moisture is generally less than 8000
feet deep and is being closely followed by drier air with
precipitable water values less than one inch. The fresh to strong
east northeast winds with gusts that could reach 35 mph will
continue today but begin to taper off tonight and Saturday.

Although precipitable water values are shown to fall off rapidly
this morning as the front moves further south, the GFS is showing
relative humidities to be solidly above 80 percent at 850 mb with
only occasional breaks. Therefore, there is some uncertainty as to
how many showers will develop after this initial frontal passage and
how long into the weekend the moisture can last. In any case
accumulations should be minor. Although PoPs have been lowered
somewhat over the forecast from 24 hours ago, scattered to numerous
showers are still in the forecast for northern and northeastern
Puerto Rico and the mountains of the interior. Lesser chances are
expected in the U.S. Virgin Islands.

&&

.LONG TERM...Monday through Saturday...

Patchy moisture remains over the area on Monday, though gradual
decreases are expected through Monday into Tuesday. An upper-level
trough is forecast to be draped across the area, largely to the
south and east of the islands, associated with a low well to the
northeast, which will support a modest level of instability.
However, dry air is expected above around 750-800 hPa, which will
preclude any significant convective development. Still, showers are
likely across the region, but decreasing through Tuesday.

With the decreased moisture, generally fair weather is likely across
the region, with fewer showers. Still, some showers are likely. East-
northeasterly to northeasterly flow is expected through Thursday.
Because of this, the greatest passing shower activity is likely to
be northeastern and eastern Puerto Rico, as well as the nearby
islands.

On Saturday, a dry slot is forecast to push southward over the
region. The steering flow is also forecast to become more north-
northeasterly. Shower activity will likely further decrease.

So, generally speaking the pattern persists, with passing showers
being the predominant form of shower activity. The level of
activity will vary based on moisture patches, whose location and
timing may change. For right now, the wettest day of the long-
term period appears to be Monday, with the driest day on Saturday.

&&

.AVIATION...
(06Z TAFS)

Drier air has moved into the area and very few showers will
develop until aft 17/22Z therefore VFR conditions are expected
everywhere except the local outer Caribbean waters. Sfc winds ENE
8 to 16 kts will bcm 11-21 kts with gusts to 28 kt on occasion aft
17/13Z. Max winds at lower levels NE 22-32 knots btwn FL004-180.
Max winds at upper levels WNW-NW 28-36 kt btwn FL365-400 and 28-38
kt btwn FL420-500.

&&

.MARINE...

A northerly swell is combining with fresh to strong winds to cause
hazardous conditions for the vast majority of the local waters. For
the waters that are exposed to the north, confused seas are likely.
Seas of up to 10 feet are anticipated, particularly for the offshore
Atlantic waters.

There is a high risk of rip currents for most local beaches,
including the USVI, Culebra, and north-facing beaches of Puerto
Rico, including Aguada and Rincon.

&&

.SJU WATCHES/WARNINGS/ADVISORIES...
PR...High Rip Current Risk through Sunday afternoon for PRZ001-002-
005-008-010-012.

VI...High Rip Current Risk through Sunday afternoon for VIZ001-002.

AM...Small Craft Advisory until 2 PM AST Sunday for AMZ710-712-715-
722-725-732-741-742.

&&

$$

SHORT TERM...WS
LONG TERM....CRS
AVIATION...WS
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Re: Caribbean - Central America Weather

#21098 Postby cycloneye » Sat Feb 18, 2023 5:34 am

Area Forecast Discussion
National Weather Service San Juan PR
507 AM AST Sat Feb 18 2023

.SYNOPSIS...
Issued at 433 AM AST Sat Feb 18 2023

Fresh to locally strong east northeast winds will continue into
next week as high pressure at the surface dominates the western
Atlantic despite the passage of a weak cold front. Shallow
moisture will be sufficient to bring occasional brief showers--
mainly to the island north of the Cordillera Central and to a
lesser extent the northern U.S. Virgin Islands--but not so much
that periods of sunshine would be precluded.

&&

.SHORT TERM...Today through Monday...

Patchy moisture is the main driver of shower activity at this point,
and will continue to be so into next week. The 00Z sounding
showed strong capping at around 800 hPa, with dry air above; this
will also persist. Though there is some instability aloft, with a
trough in the mid-to-upper levels, there is not sufficient
moisture above the cap to result in any significant convective
development. The driest day looks to be Sunday, with fewer and
weaker patches of moisture forecast to reach the islands during
the day, though Sunday night into Monday morning appears likely to
be the wettest time during the short term period.

The overall pattern is generally fair weather with occasional
showers from time to time. Forecast confidence is high.

&&

.LONG TERM...Tuesday through Sunday...

High pressure at the surface will regroup in the western Atlantic
north of the islands to maintain fresh to strong surface winds
from the northeast to east northeast until at least Friday. At
this time models promise a somewhat more relaxed pressure gradient
next weekend with winds subsiding to less than 20 mph. Also
little to no moisture is expected to appear through the end of
the period above 8 kft. Mid level temperatures will also warm
Tuesday through Thursday from minus 11 degrees to minus 4 degrees
making the airmass much more stable than now. This will preclude
heavy rains and thunderstorms through at least the end of the
month. High pressure at upper levels will also build over Cuba
causing upper level winds to turn more northerly and subside below
current velocities. Below a nearly permanent cap of 10-11 Kft,
moisture will be at or above 80 percent relative humidity--mainly
around 850-800 mb--and this will allow occasional shallow showers
to roll across the island in breezy conditions, with the best
showers generally overnight and during the early morning hours
each day. The pattern of the showers is very consistent from day
to day, but begins to fade by the end of next week.

&&

.AVIATION...
(06Z TAFS)
Issued at 433 AM AST Sat Feb 18 2023

Generally VFR conds for all aerodromes next 24 hours. Passing SHRA
expected through the period, mostly over waters, with some pushing
onshore from time to time. SHRA likely to be shallow, with moisture
ending above 8k ft; all cloud tops likely blo 11k ft. Winds
increase out of the ENE after sunrise, and likely to be gusty;
sustained wind speeds around 12 to 18 knots, higher psbl near
SHRA. After sunset, winds will weaken, to around 5 to 10 knots
overnight.

&&

.MARINE...
Issued at 433 AM AST Sat Feb 18 2023

Seas at the inner buoy have continued to be above 7 feet and seas
at the outer buoy have recently risen to close to 10 feet due to
winds of 18 to 22 knots and gusts to 25 kts. This is maintaining
seas with periods of 8 seconds. Occasional swell sets from the
north have been able to register 11 second periods, but there is
much less energy at these wave periods. Models have changed little
during the past 24 hours so have made no changes to the marine
grids. Small craft advisories may have to be extended into Monday
in the local outer Atlantic waters. Rip currents from these seas
will continue at a high risk for the northern coasts through
Sunday night, but Saint Thomas and Rincon will drop off on Sunday
night if not earlier.

&&

.SJU WATCHES/WARNINGS/ADVISORIES...
PR...High Rip Current Risk through late Sunday night for PRZ001-002-
005-008-012.

High Rip Current Risk through Sunday afternoon for PRZ010.

VI...High Rip Current Risk through late Sunday night for VIZ002.

High Rip Current Risk through Sunday afternoon for VIZ001.

AM...Small Craft Advisory until 2 AM AST Monday for AMZ710-712-715-
722-725-732-741-742.

&&

$$

SHORT TERM/AVIATION/PUBLIC...CS
LONG TERM/MARINE....WS
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Re: Caribbean - Central America Weather

#21099 Postby cycloneye » Mon Feb 20, 2023 11:10 am

Area Forecast Discussion
National Weather Service San Juan PR
438 AM AST Mon Feb 20 2023

.SYNOPSIS...Passing showers are expected to continue this morning
across the eastern portions of Puerto Rico and the USVI; and over
the local waters. Overall, stable conditions are forecasted to
prevail today and into mid-week, limiting the shower activity
across the local area for the next few days.

&&

.SHORT TERM...Today through Wednesday...

A broad mid-level ridge over the Gulf and the western Caribbean will
be the main weather feature during the short term forecast. This
will continue to promote the trade wind cap, dry air aloft and
overall stable conditions to inhibit vertical development of showers
during the next couple of days. At upper levels, a short wave trough
will move over the region today, while slowly being pushed further
eastward by the building ridge. This, however, is not expected to
have much of an influence due to the limited moisture content and
overall dry conditions at the mid-levels. Meanwhile, at the surface
a weak surface high pressure over the southwestern Atlantic and a
trough over the central Atlantic will promote an east to northeast
wind flow across the region. Embedded in this flow, areas of dry air
and patches of moisture will stream across the local area from time
to time, bringing passing showers at times over the islands.

&&

.LONG TERM...Thursday through Tuesday....

A weak cold front is forecasted to move across the local islands by
early Thursday, with minimal impacts expected associated to this
system. However, fragments of the front are expected to linger
across the area until at least late Friday. A surface high
pressure in the western Atlantic will be dominating the local
weather conditions over the weekend and mainly fair weather
conditions are expected to prevail over the local islands. The
general wind flow is forecasted to be from the east to northeast,
supporting some afternoon convection across the western and
southwestern portions of Puerto Rico with minimal shower activity.
The Precipitable Water content values between 0.75 to 0.99 inches
indicates a relatively dry pattern for the end of the workweek
into the weekend. By Monday, a second cold front is expected to
approach the forecast area with little significant change in the
weather conditions. A very dry air mass will establish across the
area, limiting shower activity and thunderstorm potential for the
long-term period and onwards. Seasonal temperatures across the
islands are expected to be near- normal values. Expect pleasant
temperatures, and nice weather.

&&

.AVIATION...Mainly VFR conditions are expected to prevail across all
terminals during the next 24 hours. However, brief trade wind
showers could move at times across TJSJ/TJBQ and the USVI terminals.
Causing mostly VCSH and SCT/BKN cigs btw FL035-FL070. Low-level
winds will continue from the ENE at 15-20 kt.

&&

.MARINE...Winds and seas will slowly subside and all small craft advisories
are expected to come down this afternoon. Seas up to 7 feet are
expected to prevail today across the offshore Atlantic waters and
the Mona Passage, and 4 to 6 feet elsewhere. However, Small Craft
will need to exercise caution due to winds and seas for much of
the period, mainly across the Atlantic waters. For beachgoers,
there is a high risk of rip currents from the northwest to
northeast facing beaches of Puerto Rico, and Saint Croix.

&&

.SJU WATCHES/WARNINGS/ADVISORIES...
PR...High Rip Current Risk through this afternoon for PRZ001-002-005-
008.

VI...High Rip Current Risk through this afternoon for VIZ002.

AM...Small Craft Advisory until 8 PM AST this evening for AMZ710.

Small Craft Advisory until 8 AM AST this morning for AMZ722-741.

Small Craft Advisory until 2 PM AST this afternoon for AMZ732.

&&

$$

SHORT TERM...DS
LONG TERM....GRS
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Re: Caribbean - Central America Weather

#21100 Postby cycloneye » Tue Feb 21, 2023 5:05 am

Area Forecast Discussion
National Weather Service San Juan PR
340 AM AST Tue Feb 21 2023


.SYNOPSIS...Mainly fair weather conditions are expected to prevail
today under partly cloudy skies across the islands. Diurnally
induced afternoon showers are expected this afternoon over
southwestern Puerto Rico, leaving minor accumulations in the
area. Seas will continue to improve today across the local waters
with seas between 4 to 6 feet. There is a moderate risk of rip
currents across most of the local beaches of the islands.


&&

.SHORT TERM...Today through Thursday...

Recent satellite imagery indicates that groups of low-level clouds
with light showers over the Tropical Atlantic will move at times
across the region during the next few days. Otherwise, diurnally
induced afternoon showers are expected this afternoon over
southwestern PR. Minor rainfall amounts are expected once again.
Thursday seems to be the best day for scattered showers across the
USVI, as PWAT peaks around 1.20 inches during the evening hours.

During the short-term forecast, the main weather feature will be a
broad mid-level ridge over the Gulf and the western Caribbean. This
ridge will continue to promote the trade wind cap, drier air aloft,
and overall stable conditions to inhibit the vertical development of
showers during the next couple of days. At upper levels, a short-
wave trough will continue moving eastward, just east and south of
the islands. However, this will have little influence due to the
limited moisture content and overall dry conditions at the mid-
levels. Meanwhile, the best available moisture will remain trapped
below 850 millibars at the lower levels. A weak surface high over
the western Atlantic and a trough over the central Atlantic will
promote an east-to-northeast trade wind flow across the local area.
The latest global guidance suggests precipitable water (PWAT) values
near 1 inch through the short-term period.

&&

.LONG TERM...Friday through Wednesday...

Remnants associated to a cold front, are forecasted to move
across the local area by Friday morning into Saturday, with
minimal rainfall accumulations expected across the northern and
eastern portions of Puerto Rico and the US Virgin Islands. A surface
high pressure in the western Atlantic will continue to be the
dominant feature across the local area, promoting mainly fair
weather conditions by mid Saturday onwards. Winds from the east to
northeast are expected to support few showers across the western
and southwestern portions of Puerto Rico. This will leave minimal
shower activity. Nonetheless, thunderstorm activity is not
anticipated to occur. The Precipitable Water content values
between 0.75 to 1.06 inches continue to indicate indicates a
relatively dry pattern will establish over the weekend, due to the
entrance of a mass of dry air into the region. By late Monday
into Tuesday, another cold front is expected to approach the CWA
with little or none significant changes in the local weather
conditions. Once this fast-moving front is out of the area, very
dry air will establish once again. This will continue limiting
shower activity and thunderstorm potential for the long-term
period and onwards. Seasonal temperatures across the islands are
expected (near-normal values). Expect pleasant temperatures over
the mountains, and nice weather across much of the islands. Dry
season in the Caribbean is knocking the door.

&&

.AVIATION...Mainly VFR conditions are expected to prevail across all
terminals during the next 24 hours. Brief -SHRA or the occasional
VCSH is possible across the USVI terminals and TJSJ through the
period. ENE winds will increase around 15 kt with higher gusts and
sea breeze variations after 21/13z.

&&

.MARINE...Moderate to locally fresh northeasterly winds will
continue to result in choppy seas aross the local waters. Seas
will remain up to 6 feet across the offshore Atlantic until at
least Wednesday. Then, seas and winds will start to improve and
seas up to 5 feet can be expected with winds up to 15 kts. Another
northerly swell is forecast by the end of the workweek into the
weekend, increasing seas and breaking waves across the coastal
areas. For beachgoers, there is a moderate risk of rip currents
from the northwest to northeast facing beaches of Puerto Rico, and
Saint Croix.

&&

.SJU WATCHES/WARNINGS/ADVISORIES...
PR...None.
VI...None.
AM...None.
&&

$$

SHORT TERM...DS
LONG TERM....GRS
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