Caribbean - Central America Weather

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cycloneye
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Re: Caribbean - Central America Weather

#21001 Postby cycloneye » Thu Nov 03, 2022 4:10 am

Area Forecast Discussion
National Weather Service San Juan PR
500 AM AST Thu Nov 3 2022

.SYNOPSIS...

A mixture of sunshine and clouds will prevail today. However, a
weak tropical wave will promote afternoon convection across the
interior and western sections of Puerto Rico, near the San Juan
Metro Area and downwind from the USVI. A polar trough approaching
from the west will promote an unstable and wet pattern Friday
through early next week. Therefore, special attention to the
forecast for this event is advised as it evolves during the next
few days.

&&

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

Ridging aloft is slightly being pushed by a polar trough that is
starting to strengthen and descend from the Eastern Seaboard;
however, drier air above the 600 mb layer will persist throughout
the day inhibiting somewhat the effects of ridge erosion at upper-
levels. At lower-levels, GOES-16 Total Precipitable Water
estimates values between 1.5 to 1.6 inches over the forecast area
which is below normal to near normal climatological levels for
this time of year and is expected to remain within these values
today. Therefore, under an east southeast steering wind flow, a
seasonal weather pattern is expected during the day with advective
showers affecting the windward coastal areas of the local islands
during the morning hours and diurnally induced afternoon showers
and isolated thunderstorms developing across the Cordillera
Central and western/northwestern Puerto Rico. The San Juan metro
area could observe heavy showers and brief isolated thunderstorms
in the afternoon as well. Streamers downwind of the smaller
islands can be expected with some brushing eastern portions of
Puerto Rico at times. Urban and small stream flooding can be
observed with this activity. Localized flash floods cannot be
ruled out.

By Thursday evening and onwards, weather conditions will gradually
deteriorate through the weekend as a complex pattern unfolds. First
the leading edge of a tropical wave, currently located over 63W,
will start to filter in the evening hours. As it moves westward, the
tropical wave will pass mostly south, but will increase moisture
content across the CWA throughout Friday. Instability aloft will
also gradually increase as the aforementioned polar trough continues
to sink in and settles northwest of the area. Dynamics aloft will
become favorable as cold air advection and a divergent pattern
establishes over the northeastern Caribbean. At low-levels, a broad
area of low pressure will start to develop west of the area inducing
a southerly flow by Friday evening. This deep-layer trough will
interact with the tropical wave and even pull additional deep
tropical moisture from the south by Friday night into Saturday.
Uncertainty remains regarding the area of maximum moisture
convergence, but models have been consistent that southeastern
Puerto Rico, Vieques, Culebra and U.S. Virgin Islands will be most
impacted by this weather pattern, with Saturday being the most
active day.

With this set up, a more enhanced convective pattern can be expected
on Friday as high moisture content and instability interacts with
surface heating during the day. The area of heaviest rain will
gradually increase with numerous showers and scattered thunderstorms
developing over interior and northwestern quadrant of Puerto Rico.
Convective activity will become widespread by Friday evening and
overnight hours. For now, model guidance has most of the activity
slowly moving eastward by early Saturday through the end of the
short-term period. However, this will all depend on where the area
of maximum convergence develops. Therefore, continue to monitor the
evolution of this forecast as this event has the potential of
causing widespread thunderstorm activity capable of producing gusty
winds and heavy rain over already saturated soils, rapid river rises
and mudslide events.

&&

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

Model guidance, once again, indicated unsettled weather
conditions from Friday (from the Short Term Period) through early
next week associated with a strong TUTT-Low lingering through late
Monday night. The confidence remains low-moderate concerning the
exact location where the rainfall maxima will occur as the ECMWF
and GFS continue flip-flopping around it. Both models suggest that
the southern and eastern sections of Puerto Rico, the U.S. Virgin
Islands, and surrounding waters have the highest potential to
observe the maximum precipitation amounts. In addition, the
National Hurricane Center (NHC) continues to closely monitor the
evolution of this event as the broad area of low pressure that
might develop in the vicinity has a low chance of tropical cyclone
formation in the next five days (20 percent). Please refer to the
latest Tropical Weather Outlook (TWOAT) issued by the NHC.

Tuesday through Thursday may be a transition period, exiting the
wet and unstable weather pattern. However, this part of the
forecast will be tight to the evolution of the area of low
pressure, which NHC is monitoring. This system could alter the
wind pattern (inducing a southerly wind flow) and may continue to
lift plenty of tropical moisture from the southeastern Caribbean
over the islands (Northeast Caribbean). Now, model guidance is
leaning toward continuing a wet and showery weather pattern
through next week's second part, pushing the plume of moisture
over the Northeast Caribbean. The confidence is still low because
it will depend on the trajectory of the moisture plume.

&&

.AVIATION...
(06Z TAFS)

VFR conditions will prevail. SHRA will affect USVI
terminals without significant impacts. Local effects will aid in the
formation of SHRA/TSRA between 03/16-22z across the interior and
western PR and downwind from El Yunque and the USVI. This activity
may affect JPS/JBQ/JSJ. Expect calm to light and variable winds thru
03/13z, and then they will return from the ESE at around 10-15kt
with sea breeze variations.

&&

.MARINE...

A small northerly swell will continue to fade across the local
waters slowly. Seas will continue up to 4 feet, and the winds out
from the east at 10 to 15 knots. However, local effects could
locally increase winds and seas each afternoon.

A tropical wave today and an upper-level trough Friday through
the early next week will deteriorate weather conditions across
the northeast Caribbean. Unsettled weather and the arrival of
another northerly swell will cause marine and coastal conditions
to deteriorate over the weekend.

For beachgoers, the risk of rip currents is moderate along the
Atlantic Coastline of Puerto Rico, Vieques, Culebra, and the
Virgin Islands. The risk of rip currents will increase to high
this weekend into early next week for most of the beaches.

&&

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

$$

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

#21002 Postby cycloneye » Fri Nov 04, 2022 3:47 pm

Area Forecast Discussion
National Weather Service San Juan PR
429 PM AST Fri Nov 4 2022

.SYNOPSIS...
A Flood Watch is in effect for Puerto Rico and the U.S. Virgin
Islands through Monday as unsettled weather conditions are
expected to prevail. There is an increased risk for flooding and
mudslides for the next several days. Marine conditions will also
deteriorate due to increasing winds and the arrival of a northerly
swell. Weather conditions will gradually improve by early to the
middle of the next workweek.

&&

.SHORT TERM...Tonight through Sunday...

Unsettled weather conditions are in the forecast due to a strong
mid to upper level trough now centered north of Hispaniola. In
fact, the circulation of this feature is evident in infrared and
water vapor satellite imagery. The trough will pull moisture from
the south, favoring periods of showers and thunderstorms across
the islands. As a result, a Flash Flood Watch is in effect. Since
the soils are already saturated, additional rains will increase
the risk for urban, river and flash flooding, as well as mudslides
in areas of steep terrain. Due to the instability generated by
the mid and upper level trough,a surface low pressure should
develop north of the area, which should maintain a moist southerly
flow prevailing through the weekend. The high resolution and
global models agree on the wet pattern, but there are
discrepancies in timing, amounts and location of the heaviest
activity. So far, the southern and eastern portions of Puerto
Rico, as well as Vieques, Culebra and the United States Virgin
Islands should experience the bulk of the even, although all the
region will be prone to flooding. The users are advised to stay
tuned to further updates in the forecast during the weekend.

&&

.LONG TERM...Monday through Friday.../modified from prev
discussion/

The unsettled weather conditions may continue on Monday. Suppose
the flooding rains event occurs throughout the weekend. In that
case, saturating even more the soils and increasing the
streamflows along local rivers, the risk of flash flooding and
mudslides will extend through at least Monday evening. The
confidence in the model guidance is moderate because the event is
tight to the upper-level feature's final position and the
surface's low-pressure evolution. That non-tropical low is being
monitored by the National Hurricane Center (NHC) and might develop
near the Northeast Caribbean or the Western Atlantic. It has a
medium chance of tropical cyclone formation in the next five days
(40 percent). Please refer to the latest Tropical Weather Outlook
(TWOAT) issued by the NHC.

This non-tropical low plays an essential role in the islands'
weather scenario. Therefore, the confidence in next week's weather
scenario is even lower due to high uncertainty about this
system's future path/intensity. However, GFS solution insists on a
southerly to southwesterly wind flow through late Wednesday
night, from the southeast on Thursday, and more easterly by
Friday. Moisture content is now even lower than the previous run
cycle, and the upper-level dynamic seems weaker. Therefore, this
period could be a transition to better weather conditions with
just the typical afternoon convection.

&&

.AVIATION...VFR cond will prevail at all terminals. FQT passing
SHRA/Isold TSRA with SCT-BKN multi lyr cld lyrs nr FL025... FL050.
BKN OCNL OVC nr FL100 across the local flying area. SHRA/Isold TSRA
will cont VCTY of USVI and terminals.Aftn convection will continue
to affect the eastern, central and nrn half of PR, including the
TJSJ/TJBQ/TJNR terminals til at least 04/23Z. Brief MVFR expected
at most terminals with Mtn Top obscr across the ctrl mtn range of
PR. E-SE wnds btw 10-15 kts with ocnly hir gusts especially with
convective activity.

&&

.MARINE...
Seas and winds are expected to increase tonight and tomorrow above
small craft advisory criteria for the offshore waters, local
passages and the waters north of the Virgin Islands. Expect seas
up to 8 feet and sustained winds out of the south at 20 to 25
knots this weekend. Unsettled weather conditions are expected for
the local waters as well, and seas could become locally hazardous
close to the thunderstorms. For the beaches, the risk of rip
currents will increase to high for southeastern Puerto Rico and
Culebra tomorrow, and the high risk will stretch further on
Saturday night and Sunday.

&&

.SJU WATCHES/WARNINGS/ADVISORIES...
PR...Flash Flood Watch through Monday afternoon for PRZ001>013.

High Rip Current Risk from Saturday morning through Saturday
afternoon for PRZ003-012.

VI...Flash Flood Watch through Monday afternoon for VIZ001-002.

&&

$$

SHORT TERM...DS
LONG TERM....ERG
PUBLIC...MMC
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Re: Caribbean - Central America Weather

#21003 Postby cycloneye » Mon Nov 07, 2022 4:40 am

Area Forecast Discussion
National Weather Service San Juan PR
512 AM AST Mon Nov 7 2022


.SYNOPSIS...
Scattered showers are forecast to affect portions of the USVI, as
well as southern and eastern PR for the next few days. The Flash
Flood Watch continues in effect as the soils are still very
saturated and as additional rain is expected. However, the
significant shower activity that could happen is expected to be
relatively isolated. A return to a seasonal pattern is forecast by
the end of the week as the general wind flow becomes easterly
along with climatologically normal moisture across the region.


&&

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

The surface low pressure is to the north of the local area,
bringing a line of moisture and shower activity over the local
area. Most of the shower and isolated thunderstorms have remained
over the waters. but scattered showers are forecast to affect
portions of the USVI, as well as southern and eastern PR over the
next several days.

The narrow band of deep moisture could widen over the next few
days, having not only eastern PR and the USVI under some moisture,
but also south central to southwestern PR with a light southerly
wind flow. This general pattern will be relatively similar each
day through the short term period, except that the latest guidance
has Tuesday night into Wednesday as a relatively dry night, but
Wednesday during the day has a good amount of moisture over PR,
and drier air for the USVI. By then, the upper trough is expected
to be relatively broad and weaker than it is now, so thunderstorm
development is expected to be isolated even though mostly cloudy
skies and numerous showers would be expected.

The Flash Flood Watch continues in effect as the soils are still
very saturated and additional rain is expected across the USVI,
and eastern and southern PR. However, the significant shower
activity that could happen is expected to be relatively isolated.

&&

.LONG TERM..Thursday through Tuesday...

The weather pattern is starting to return to a typical seasonal
pattern as the lower level wind trade wind flow returns. Abundant
moisture remains in the region as multiple previous days of
southerly flow prevailed. On Thursday, winds from the southeast
will result in windward passing showers across eastern/southern
sections and then afternoon convection with thunderstorms across
the interior/northwestern sections of Puerto Rico. Eastern
sections may experience heavier afternoon activity due to streamer
formation off of El Yunque, the Cayey Mountain Range, and the
smaller islands. By Friday, the lower level wind flow will return
to the climatological flow, from the east. A very similar weather
pattern is expected in respect to the day before, however
convection may concentrate more in the interior/central western
sections of Puerto Rico.

GFS model guidance indicates a drier trend by the weekend as
precipitable water values drop and a mid to upper level ridge
builds to the west over Hispanola, which may aid in atmospheric
stability. This combination of factors would result in the typical
regime of passing windward shower followed by afternoon
convective activity and streamer formation. Rainfall will be
limited, however afternoon storms could produce locally
significant rainfall. Overall, a return to a seasonal pattern is
forecast.

&&

.AVIATION...VFR conds are expected today across the local
terminals. VCSH is forecast across the USVI terminals as well as
TJSJ and TJPS, but significant TSRA development is not expected
today over the terminals. CIGs at around FL060 could be observed
today across TIST, TISX, TJPS and TJSJ. Winds will be generally
light, at around 10KT or less, with a strong southerly component.

&&


.MARINE...A northerly swell and wind wave energy is currently
maintain wave heights up to 10 feet across the local waters, with
the greatest heights across the Offshore Atlantic. The swell
peaked out yesterday afternoon and is currently measuring at
around 4 feet at 11 seconds, taken from the northern coast
nearshore buoys. It is expected to linger until midweek, fading
out by Wednesday. Moderate to locally fresh southerly winds will
prevail for the next couple days.

Due to these hazardous marine conditions, a Small Craft Advisory
is in effect for the Offshore Atlantic Waters Today and this
morning for the waters near the USVI. There is also High Risk of
Rip Currents advisories out the the northern facing coastline of
Puerto Rico from Rincon to Luquillo. The risk is moderate
elsewhere.

&&


.SJU WATCHES/WARNINGS/ADVISORIES...
PR...Flash Flood Watch through this afternoon for PRZ001>013.

High Rip Current Risk through late tonight for PRZ001-002-005-
008.

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

VI...Flash Flood Watch through this afternoon for VIZ001-002.

High Rip Current Risk through this afternoon for VIZ002.

&&

$$

SHORT TERM...JA LONG TERM....RC
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Re: Caribbean - Central America Weather

#21004 Postby cycloneye » Tue Nov 08, 2022 4:43 am

Area Forecast Discussion
National Weather Service San Juan PR
510 AM AST Tue Nov 8 2022

.SYNOPSIS...
Rainfall is expected to affect southern and eastern PR as well as
the USVI today and tomorrow as deep moisture continues to
encompass the region. By Thursday, the local winds are expected to
be more easterly, and the weather pattern could become a bit more
typical. The return to a more seasonal pattern is forecast for
Friday into next week with a possible drier trend late next week.
A strong northerly swell is expected to peak across the local
waters on Friday night, causing hazardous marine conditions.

&&

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

Subtropical storm Nicole is well to the north of the local area,
but it is pulling moisture from the south and over the local area,
causing a line of shower and thunderstorm activity over the local
area to affect the local islands at times. Tonight, the line of
showers affected the USVI, leaving up to 2 inches of rain in some
areas, and there is still the possibility of a similar scenario to
affect PR and the USVI today and tomorrow.

The band of deep moisture will encompass the local islands today
and tomorrow, though most of the rainfall is expected to affect
southern and eastern PR as well as the USVI. That said, the latest
guidance has Wednesday during the day with some moisture over PR,
but drier air for the USVI as winds shift a bit to a SE
direction. So the USVI has a better chance of rain today and
tonight than it does on Wednesday onward. By Thursday, the local
winds are expected to be more easterly, and the weather pattern
could be a bit more typical. There will still be good moisture,
and with the easterly winds, some locally induced shower activity
could affect portions of central and western PR in the afternoon,
while fair weather would be expected for the USVI during the day,
then scattered brief showers during the night.

&&

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

By this time, Subtropical Storm Nicole will have moved far from
the region, causing a lose of influence over the local wind flow.
By Friday afternoon, the lower level wind flow is expected to
return to a general east/southeasterly direction with localized
sea breeze variations during the afternoon hours across coastal
areas. This surface southeasterly flow will continue throughout
the long term period as a broad area of high pressure builds
across the surface of the Central Atlantic. This feature will
enhance stability through the upper to mid levels across the
Eastern Caribbean, which will help limit thunderstorms.
Precipitable water values are forecast to be average to above-
average as an area of lower pressure to the north recycles some
moisture over the region over the weekend and as a plume of
moisture passes south of the region on Monday.

Each day during this period, a regime of passing windward showers
across the USVI and southeastern/eastern sections of Puerto Rico
supplemented with afternoon convective activity is forecast.
Seabreeze convergence, orographic lifting, and diurnal heating
will result in scattered shower and thunderstorm activity across
the interior to west/northwestern sections of Puerto Rico. Also
during the afternoons, persistent bands of showers, "streamers",
are likely to form downwind of landmass such as El Yunque, the US
Virgin Islands, Culebra, Vieques, and the Cayey mountain range.
Rainfall maximums are expected over the weekend and into the start
of the week before drier air arrives by Wednesday. Overall, a
return to a seasonal pattern is forecast.


&&

.AVIATION...VFR conds are expected today across the local
terminals. VCSH is forecast across the USVI terminals as well as
TJSJ and TJPS, but TSRA development is possible expected today
over the terminals, especially in the afternoons, so VCTS is
forecast for TJSJ, TJPS, TIST, and TISX after 08/16Z. CIGs at
around FL060 could be observed today across TIST, TISX, TJPS and
TJSJ. Winds will be generally light, at around 10KT or less from
the south

&&

.MARINE...A fading northerly swell and light to moderate southerly,
shifting southeasterly, winds will continue to cause choppy seas
across the local waters for the next couple days. Unsettled
weather conditions will result in periods of showers and
thunderstorms with areas of locally heavy rains across the
regional waters and local passages throughout the week. Wind flow
will remain from the south/southeast until Friday when becoming
mostly easterly. A strong northerly swell is expected to start
reaching the local waters by late Thursday, peaking out Friday
night. Marine conditions will rapidly deteriorate due to this
swell by Friday.

The High Risk of Rip current Advisory is ending this morning for
the northern coastline of Puerto Rico. The risk will then be
moderate for all local beaches across Puerto Rico and the USVI.


&&

.SJU WATCHES/WARNINGS/ADVISORIES...
PR...High Rip Current Risk until 6 AM AST early this morning for
PRZ001-002-005-008.

VI...None.

&&

$$

SHORT TERM/AVIATION...JA LONG TERM/MARINE...RC
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Re: Caribbean - Central America Weather

#21005 Postby cycloneye » Wed Nov 09, 2022 5:05 am

Area Forecast Discussion
National Weather Service San Juan PR
451 AM AST Wed Nov 9 2022

.SYNOPSIS...
Due to a band of deep moisture, rainfall is expected to affect
southern and eastern PR, as well as the USVI for brief periods. A
typical weather pattern of passing windward showers and afternoon
convection is forecast to return by tomorrow, lasting throughout
next week. A strong northerly swell is forecast to reach the local
waters by Friday, causing hazardous coastal and marine
conditions throughout the weekend.

&&

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

Tropical storm Nicole is well to the northwest of the local area,
but it continues pulling moisture from the south and over the
local area, causing a line of shower and thunderstorm activity
over the local area, mainly affecting the Caribbean waters and
east and south Puerto Rico over the past several hours.

The band of deep moisture will encompass the local islands today,
but most of the rainfall is expected to affect southern and eastern
PR, as well as the USVI for brief periods. The latest guidance has
moisture moving over the local area today, under a SE wind flow, but
gradually drier air moving in for the USVI this evening. So the USVI
has a better chance of rain today than tonight and onward. By
Thursday and Friday, the local winds are expected to be easterly,
and the weather pattern could be a bit more typical. There will
still be good moisture on Thursday, but a drier patch could move in
during the day on Friday. This pattern on Thursday and Friday would
allow for locally induced showers and thunderstorms over central to
western PR in the afternoons, though limited moisture on Friday
would mean much less coverage or intensity of the showers. The USVI
would have isolated to scattered brief showers under this pattern on
this latter part of the workweek.


&&

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

A surface high pressure system in the Central Atlantic will drive
easterly trade winds across the region for the following several
days. Precipitable water values remain average to above-average
over the weekend into the beginning of next week, resulting in
enough fuel for a regime of passing windward showers across the
USVI and eastern sections of Puerto Rico supplemented with
afternoon convection. Each day the greatest amounts of rainfall
can be expected across the interior/western sections of Puerto
Rico due to seabreeze convergence and local effects. On Monday, a
tropical wave will pass through the Eastern Caribbean, enhancing
shower and thunderstorm activity across the local Caribbean
Waters. GFS guidance shows a Tropical Upper Tropospheric Trough
(TTUT) to the northeast on Tuesday. The current positioning of
this feature would not make much of an impact locally, however if
it positions closer to the region, Tuesday may become a wetter
day. By Wednesday, a dry airmass is forecast to move in,
significantly improving weather conditions across the islands.


&&

.AVIATION...VFR conds are expected today across the local
terminals. VCSH is forecast across the USVI terminals as well as
TJSJ and TJPS, but TSRA development is possible today, but will
handle with AMD as there is uncertainty on exact timing and
proximity to the terminals. Winds will be from the SE at around
10KT with sea breeze variations.

&&

.MARINE...Moderate southeasterly winds and a small northerly
swell will maintain wave heights around 5 feet across the local
waters. The local wind flow is expected to become easterly by
Friday. A strong northerly swell will start to enter the local
waters by Thursday night, with wave heights peaking out on Friday
Night. Expect hazardous coastal and marine conditions during this
time. Today, the risk of rip currents is moderate across all
beaches of Puerto Rico and the USVI.


&&

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

&&

$$

SHORT TERM...JA
LONG TERM....RC
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Re: Caribbean - Central America Weather

#21006 Postby cycloneye » Thu Nov 10, 2022 3:57 am

Area Forecast Discussion
National Weather Service San Juan PR
429 AM AST Thu Nov 10 2022


.SYNOPSIS...
A more seasonal pattern is expected to prevail as winds
reestablish from the southeast, then from the east by the end of
the week. Marine conditions will deteriorate by tomorrow as a
northerly swell arrives from the north. Another tropical wave is
forecast to cross the islands by Monday and Tuesday.

&&

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

As Hurricane Nicole continued to quickly reach the east coast of
Florida this morning, a weak tropical wave will enter the eastern
Caribbean later today, followed by an induced low level trough
Friday into Saturday. In the meantime a mid to upper level ridge
will build and hold across the region during the period while a
upper trough (Tutt) is forecast to become amplified just east of the
region late Friday into Saturday. The present synoptic pattern will
therefore continue to gradually change during the period as the low
level winds and steering pattern become southeast to east today,
then more east-northeast by Friday and Saturday.

For the rest of the morning hours passing showers carried by the
east southeast trades will affect the coastal waters and mainly the
windward side of the islands including the USVI. However rainfall
accumulations are not expected to be significant as showers will be
brief. During the rest of today, expect sufficient moisture
availability to aid in locally and diurnally induced afternoon
convection. This should be focused over parts of the central
interior and west sections of PR steered by the moderate trade wind
flow. Periods of locally heavy rains over these areas may lead to
minor urban and small stream flooding as well as ponding of water on
roads and in poor drainage areas with mudslides still possible in
areas of steep terrain.

By Friday and Saturday, as previously mentioned, the local winds are
expected to become easterly, and overall the weather pattern is
forecast to be more seasonal. However the occasional surges of
additional tropical moisture trailing the tropical wave and
accompanying the aforementioned surface trough will be sufficient to
support more frequent evening and morning showers over the coastal
waters and east sections of Puerto Rico and the USVI. This will be
followed by locally and diurnally induced afternoon convection
mainly over the west sections of Puerto Rico although some shower
development will remain possible in and around the San Juan metro
and mainly downwind and on the west end of the USVI. The heaviest
rainfall should however be over central and west PR each day where
urban and small stream flooding will remain possible. The USVI
should experience brief isolated to scattered afternoon showers but
no significant rainfall accumulations are so far expected during the
period at this time.


&&

.LONG TERM...Sunday through Friday...
A surface high pressure centered along the northeastern Atlantic
will maintain the wind flow out of the east-southeast, while an
upper level ridge builds north of the region. The weekend will end
with seasonable weather conditions. The trade winds will push
patches of moisture across the region, but with drier air at the
mid and upper levels. Local effects and diurnal heating should be
enough to generate afternoon convection, mainly along the interior
and western Puerto Rico, and downstream from the Virgin Islands.
By early in the workweek, moisture increases as a tropical wave
approaches. A shortwave trough is also apparent in the latest GFS
run, which works to increase instability aloft. Additionally,
precipitable water values are expected to be above normal on
Monday and Tuesday, hence there is an increase potential for
showers and thunderstorms affecting the islands. Once the tropical
wave departs, another surface high exiting the eastern coast of
the United States will shift the low level winds from the
northeast while the steering flow strengthen a little. A drier
air mass will filter in by then, but under northeast winds, an
advective pattern is favored, with showers moving in at times
along the northern coast of Puerto Rico and across the USVI in the
overnight and early morning hours.


&&

.AVIATION...
VFR conds will persist durg the period with wdly SCT -SHRA/SHRA ovr
regional waters and enroute btw islands and VCSH at TJPS/TISX/TIST
til 10/12Z. Winds will be calm to light and variable bcmg fm ESE at
10-15 kts with sea breeze variations aft 10/14Z. Aftn convection
expected fm 10/17-22z) mainly downwind fm the the USVI and El Yunque
which may impact TIST/TISX/TJSJ. Mtn Top obscr and SHRA/Isold TSRA
may also develop across the Central mtn range of PR and over W PR.

&&

.MARINE...
Local buoys show seas up to 3 feet, while the offshore Atlantic
buoys show seas up to 5 feet (41046) and up to 9 feet ( 41059).
A northerly swell is expected to reach the local Atlantic waters
by tomorrow, and seas will become hazardous, increasing up to 7
feet. For the local beaches, the risk of rip currents is moderate
along northern Puerto Rico, Culebra and St. Croix.

&&

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

$$

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

#21007 Postby cycloneye » Fri Nov 11, 2022 4:33 am

Area Forecast Discussion
National Weather Service San Juan PR
355 AM AST Fri Nov 11 2022


.SYNOPSIS...
A more seasonal pattern is expected to persist for the next few
days across the islands. A tropical wave is expected for early
next week, once again increasing showers and thunderstorms. Marine
and coastal conditions will be deteriorated today and into the
weekend due to the arrival of a northerly swell.

&&

.SHORT TERM...Today through Sunday...
Mid to upper level ridge will remain in place across the region
through Saturday. This will gradually erode by Sunday as a TUTT is
reinforced by a short wave trough north of the region and becomes
amplified over the northern Leeward islands and east of the
areas. Surface high pressure ridge settling north of the region
over the west central Atlantic will maintain an east to northeast
local wind flow, as an easterly perturbation crosses the area
later today into Saturday, followed by a tropical wave is forecast
to enter the eastern Caribbean by Sunday afternoon. This will
result in increasing low level moisture convergence across the
region and thus more frequent passing showers during the morning
hours with better chance for enhanced afternoon and overnight
showers on Sunday.

For today a more typical and seasonal weather pattern is expected
with some passing morning showers affecting the coastal waters and
parts of the east coastal areas from time to time. Local terrain
effects and daytime heating along with lingering pockets of moisture
will support scattered to numerous afternoon convection over parts
of the interior and southwest sections of Puerto Rico as well as in
isolated areas of the San Juan Metro. Main impacts will be the
chance of minor urban and small stream flooding and ponding of water
on roads and poor drainage areas particularly across the central and
southwest sections of Puerto Rico. Lesser activity expected in and
around the USVI today and afternoon convection should be mainly on
the west-end and downwind of the islands.

For the weekend... The amplifying TUTT east of the region and the
forecast passage of an induced easterly perturbation will be more
than sufficient to maintain periods of occasional passing morning
showers across the coastal waters, with some affecting the
coastal areas from time to time. However the frequency and
intensity of these showers and the afternoon convection is so far
expected to increase and become more enhanced by late Saturday and
Sunday as the upper ridge gradually erodes and moisture
convergence is forecast to increase by late Saturday and Sunday in
advance of a tropical wave. Consequently better chance for minor
urban and small stream flooding across portions of the islands but
mainly central and west PR, as well as ponding of water on roads
and in poor drainage areas over the USVI. Again the potential for
mudslides and unstable terrain and will persist trough the weekend
due to continued saturated soil conditions across much of the
forecast area.

&&

.LONG TERM...Monday through Saturday...
A shortwave trough exiting the eastern coast of the United States
should be positioned north of the islands on Monday, while a
tropical wave, along with a wind surge, approaches from the east.
Precipitable water values are expected to remain above 2.0 inches,
which is above normal for this time of year, with the columnar
moisture stretching into the mid-levels of the atmosphere. These
ingredients should result in a wet start for the workweek, with
showers reaching the Virgin Islands and most of Puerto Rico. By the
middle of the workweek, the atmosphere dry out at the mid levels as
a ridge begin to builds over the western Caribbean. A surface high
pressure begins to get established north of the islands, and winds
will gradually shift from the northeast while the steering flow also
increases a bit. During this period, conditions will become less
favorable for strong shower activity across the region.
Nevertheless, under a northeast wind flow, an advective pattern will
prevail, with passing showers moving in the overnight and morning
hours across eastern and northern Puerto Rico and across the U.S.
Virgin Islands. A similar pattern is expected to continue all the
way into the end of the workweek and early in the weekend.

&&

.AVIATION...
VFR conds will persist durg prd with Isold-SCT -SHRA/SHRA ovr coastal
waters and TJSJ/TISX/TIST at times with winds calm to lgt/vrb til
10/14z, then bcmg fm E/NE at 10-15 kt with sea breeze variations.
Afternoon convection (11/16-22z) fcst mainly downwind from the USVI
terminals and El Yunque in PR which may briefly impact TJSJ with
limited MVFR due to SHRA. Also, mountain obscr due to Isold
TSRA/SHRA may form across the Central Mtn range and ovr W PR,
impacting TJBQ/TJMZ.

&&

.MARINE...
The most recent observations from the offshore buoys show a
northerly swell advancing toward the local Atlantic waters. Seas
are expected to be hazardous today, increasing up to 7 feet. These
conditions are expected to spread into the weekend.

Coastal conditions will deteriorate as well, with breaking waves
reaching 10 feet, just enough criteria to issue a High Surf
Advisory for northern Puerto Rico, Culebra and the northern U.S.
Virgin Islands. There is a high rip current risk for the northern
coast of the local islands.


&&

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

High Surf Advisory from 6 PM this evening to 6 PM AST Saturday
for PRZ001-002.

High Surf Advisory until 6 PM AST Saturday for PRZ005-008.

High Rip Current Risk from this evening through late Saturday
night for PRZ010.

High Surf Advisory from 8 PM this evening to 6 PM AST Saturday
for PRZ012.

VI...High Rip Current Risk from this evening through Saturday
afternoon for VIZ001.

High Surf Advisory from 6 PM this evening to 6 AM AST Saturday
for VIZ001.

&&

$$

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

#21008 Postby cycloneye » Sat Nov 12, 2022 5:27 am

Area Forecast Discussion
National Weather Service San Juan PR
513 AM AST Sat Nov 12 2022


.SYNOPSIS...

A more seasonal pattern is expected to persist for the rest of the weekend
across the islands. Another tropical wave is expected for early next
week, once again increasing showers and thunderstorms. Hazardous marine
and coastal conditions will continue today through Sunday to due to
the arrival of a northerly swell and moderate easterly winds.

&&

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

A mid to upper level ridge located north of Hispaniola will
continue to migrate toward our area, promoting a drier air mass at
these levels. However, just east of the Leeward Islands, there is
an upper level trough. This system could induce a few patches of
moisture that will be dragged by the trade winds across the islands.
The first patch for this period should arrive early today. This feature
will bring some low level convergence, increased moisture levels and
a low level steering flow out of the east-northeast. Therefore, expect
passing showers affecting eastern Puerto Rico and the United States
Virgin Islands through the day, but the strong convection should
be limited to the southwestern quadrant of Puerto Rico. Keep in
mind that soils are still saturated, and any period of heavy showers
could lead to mudslides, urban flooding and rapid river rises.

By Sunday, the ridge moves just north of the local islands while moisture
decreases a little. As a result, the high resolution and global models
are showing less accumulation across the islands. Nevertheless, a
similar pattern of showers is expected, just that the activity should
not be as strong or last too long. Then, by late Sunday into Monday,
a tropical wave will approach the northeastern Caribbean. The axis
of this wave should cross the region by early Monday, shifting the
winds from the east- southeast. This feature is expected to increase
the frequency of showers and isolated thunderstorm activity throughout
the day, which will enhanced the potential for additional flooding,
mudslides and rapid river rises.

&&

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

A shortwave trough will continue to reinforce a Tutt northeast of
the area through Tuesday, while a tropical wave exits the region
and is followed by a wind surge from the east. Recent model guidance
continued to suggest layered precipitable water values above normal
at least into Wednesday and was ranging between 1.80-2.0 inches.
Trade wind moisture will therefore continue to be transported
across the area by the moderate trade winds and enhanced by the
lingering Tutt northeast of the region. That said there will be
more than sufficient moisture available for passing showers to
affect the local waters and reach portions of the north and east
coastal sections during the evening and overnight hours, followed
by afternoon convection each day. The heaviest rainfall is
forecast to be over parts of the central and west to southwest
interior of Puerto Rico steered by the prevailing east to
northeast winds. Brief showers around the San Juan metro cannot be
ruled out as some may develop in the afternoon over the east
interior then later stream westward across these areas. This
however should be of short duration with no significant
accumulations expected at this time. The U.S Virgin Islands should
expect more typical passing morning showers each day, followed by
mostly isolated afternoon showers on the west-end and downstream
of the islands. Minor urban and small stream flooding and ponding
of water on roads and in poor drainage areas will remain possible
for portions of the islands at least through Tuesday. Widespread
flooding is however not expected but mudslides in areas of steep
terrain should remain a concern due to saturated soil condition.

By Wednesday a through the rest of the work week, a gradual erosion
of the overall moisture content is forecast as the local airmass
is expected to dry out and the mid to upper level ridge builds
across the region from the western Caribbean. This along with a
surface high pressure reestablishing north of the islands will
cause winds to gradually shift and become more northeasterly while
slightly increasing. This will favor a more seasonal advective
pattern with the possibility of occasionally enhanced morning
shower activity across the region. A similar pattern is expected
to continue all the way into the following weekend, except that
the Tutt and an associated upper low is to so far forecast to
develop by the latter part of the weekend and retrograde westward
across the region and into the eastern Caribbean. This in turn
will increase the chance for thunderstorm develop across the
region by Sunday when another tropical wave is forecast to
approach the Lesser Antilles.

&&

.AVIATION...
VFR conds will prevail at all terminals durg prd. VCSH are expected
to affect the USVI and TJSJ terminals til 12/14Z, but no sig
operational wx impacts are fcst. Fm 12/17Z-22Z, SHRA/Isold TSRA
are expected to develop mainly ovr the western half of the Cordillera
Central of PR, causing brief mountain top obscuration. VCSH also
psbl at TJPS/TJBQ/TJMZ and may result in periods of reduced VIS
and low ceilings. Winds will be mainly fm the east around 10 kts
aft 12/14Z with variations due to sea breeze variations and ocnl
hir gusts til 12/22Z.

&&


.MARINE...

Conditions will continue to deteriorate today due to the arrival
of a northerly swell which will spread across the local Atlantic
Waters and Mona Passages. This northerly swell is increasing seas
to between 6-8 feet across the Atlantic waters with occasional
seas up to 10 feet. Therefore, a Small Craft Advisory is in effect
for these waters and small craft should exercise caution elsewhere
due to gentle to moderate trade winds and a moderate chop.

For the beachgoers, hazardous surf zone conditions will continue
due to dangerous breaking waves possibly nearing 10 feet and the
risk of rip currents will become high along beaches of the Atlantic
Coastline.

&&

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

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

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

High Rip Current Risk through this afternoon for VIZ001.

&&

$$

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

#21009 Postby cycloneye » Sun Nov 13, 2022 5:27 am

Area Forecast Discussion
National Weather Service San Juan PR
502 AM AST Sun Nov 13 2022

.SYNOPSIS...
An induced surface trough will continue westward across the region
today through Monday morning followed by a wind surge on Tuesday, as
high pressure will build north of the region and increase the easterly
trade winds across the area. The mid to upper level ridge in place will
gradually erode today through Monday, as a short wave trough crosses
just north of the region and amplifies a Tutt located northeast of
the region. A subsiding northerly swell and gentle to moderate trade
winds will continue to cause choppy seas mainly across the offshore
Atlantic waters and local passages.

&&

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

A surface trough crossing the islands and a high pressure centered
over the north-central Caribbean are maintaining a northeasterly
wind flow. At the mid and upper levels, a ridge is promoting a drier
air mass, while and upper level trough remains positioned just to
the east of the Lesser Antilles. Recent satellite imagery show that
most of the cloudiness and shower activity is currently reaching the
Leeward Islands. For this morning, advective showers will prevail
across northern Puerto Rico and the U.S. Virgin Islands. Although
conditions are the upper levels are not particularly favorable for
strong convection, diurnal heating and local effects should be
enough to cause a few areas of strong showers and isolated
thunderstorms across the interior and western Puerto Rico. Late this
afternoon and evening, as the surface trough continues to move
through, the low level wind flow will shift from the southeast, and
shower frequency will increase across the United States Virgin
Islands and later spreading over eastern and southern Puerto Rico.
So far, the GFS has the main bulk of the moisture field crossing the
islands on Monday and early Tuesday. Although this event is not
expected to be as significant as the one in early November, recent
data from the USGS river monitors still indicate that the rivers are
running above normal to much above normal value. Any period of heavy
rain could result in urban flooding, mudslides and rapid river
rises.

&&

.LONG TERM...Wednesday through Monday...

Wednesday through the rest of the work week, a gradual erosion of
the overall columnar moisture content is forecast, as the local
airmass is expected to slowly dry out and the mid to upper level
ridge builds and remain in place across the region thus favoring
overall stable conditions aloft. This along with a surface high
pressure reestablishing north of the islands will cause winds to
gradually shift and become more northeasterly while increasing in
intensity becoming breezy at times. This will favor an east to
northeast wind flow and more of a seasonal advective pattern, with
the possibility of occasionally enhanced morning showers over the
local waters and coastal areas during the period.

Similar conditions are so far expected to persist into Saturday but
by the latter part of the weekend (Sunday afternoon onwards) the pattern
is to slowly change as an amplifying TUTT and a developing upper low
is forecast to retrograde westward across the region and into the
eastern Caribbean. This in turn will increase the chance for more
frequent shower activity and thunderstorm development across the
region by Sunday and Monday, when yet another tropical wave and
induced low level trough is forecast to approach the Lesser Antilles.
During the period...Minor urban and small stream flooding and ponding
of water on roads and in poor drainage areas will remain possible
for portions of the islands,but more so from Sunday into the early
part of the following week as a Tutt low and tropical wave will
approach the region as previously mentioned. Widespread flooding
is however is so far not expected but mudslides in areas of steep
terrain should still remain a concern due to saturated soil conditions
particularly in higher terrain.

&&

.AVIATION...
VFR conds will prevail across the local terminals. VCSH at most
terminals except for TJPS til 13/14Z due to passing trade wind
SHRA. Low level wnds fm NE 5-15 kts BLO FL200 then backing and
incr w/ht ABV. SFC wnds calm to light and variable bcmg fm east
northeast at 10-15 knots with sea breeze variations aft 13/14Z.
Aftn convection fcst to develop across the central interior and
western sections of interior and W PR with VCTS psbl at
TJBQ/TJMZ...VCSH at TJPS and mainly downwind of USVI terminals.

&&


.MARINE...

A subsiding northerly swell will cause seas to gradually improve
today, with seas becoming 5 feet or less today. However the gentle
to moderate winds 5-15 KT will continue across the local waters to
maintain a light to moderate chop mainly over the offshore waters
and local passages. There is still a high risk of rip currents until
later this afternoon across the northern beaches of PR and Culebra,
while a moderate risk will continue for the USVI beaches and the
remaining beaches except for the south coastal beaches of PR where
the risk of rip currents will be low.

&&

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

VI...None.

&&

$$

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

#21010 Postby cycloneye » Mon Nov 14, 2022 4:53 am

Area Forecast Discussion
National Weather Service San Juan PR
546 AM AST Mon Nov 14 2022

.SYNOPSIS...

Moisture is approaching the region, and is expected to affect the
islands through the day today. This will result in an increase in
shower activity, with scattered to numerous showers and isolated
thunderstorms. Persisting moisture is expected for tomorrow, with
a drying trend for midweek into the weekend.

&&

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

A trough in the lower levels will bring increasing moisture in the
east southeast to southeast flow. A second weaker wave will move
through on Tuesday. Moisture will diminish significantly from
midnight tonight to Wednesday noon with precipitable water
decreasing from 2.1 to around 1.4 inches. Expect the best rains to
be today, Monday with some showers lingering into tonight. Some
urban and small stream flooding is likely in western Puerto Rico
this afternoon. Low-level winds will gradually back around to
easterly by late Wednesday night, as a cold front over the western
Atlantic lifts over the central Atlantic high and trade winds flow
becomes less deflected around the southwest portion of the high
pressure at the surface.

Upper level features are weak and will generally see high pressure
over the central Caribbean and a trough over the Antilles that will
be joined by a weak trough crossing over the local area tonight and
sending the TUTT on an eastward trek through Wednesday. Late
Wednesday night however another shortwave will drop into its place
so winds at 250 mb will remain northwest to north north northwest
through the period. This will give little additional enhancement to
the showers that will continue around the area in the easterly flow.

&&

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

Patchy moisture will continue over the area into the end of the
workweek. Moisture values will be near normal to just below normal
during this time, though a trend of decreasing amounts is expected.
This decrease in moisture will continue through Saturday, as well,
when below-normal moisture is likely for much of the region. Aloft,
a mid- to upper-level ridge is forecast to be over the region
through the end of the week, resulting in stability. Therefore,
though a typical pattern of moisture is expected, activity will
decrease into the end of the week, with limited activity on Saturday.

Meanwhile, an upper-level low is forecast to move southeast from
over the Atlantic to just east of the Windward Islands by this
weekend. During this time, troughing is induced in the mid-levels
and into the lower levels. This troughing will move westward during
the weekend, approaching the region on Sunday into Monday. On
Monday, the upper-level low is forecast to be just southeast of the
islands. This will result in increasing instability and therefore
support aloft for convective activity. Gradual increases in moisture
are expected during the day on Sunday, with a significant increase
in moisture late in the day as the induced surface trough pushes
toward the region. As such, a modest increase in shower activity is
anticipated for Sunday. Moisture will continue to increase during
the night Sunday into Monday; because of this, it is currently
likely that Monday will bring active weather to the region.

&&

.AVIATION...
(06Z TAFS)

Sct SHRA will incrs from SE to NW across PR with sct SHRA arnd
the USVI. SHRA coverage and intensity will incrs durg the day
through 15/02Z with brief MVFR conds and mtn obscurations. Isold
TSRA aft 14/16Z. Sfc winds ESE 10-15 kt with ltd sea breezes. Max
winds NW 30-40 kt btwn FL360-460.

&&

.MARINE...

A northeasterly swell continues to affect the local Atlantic waters
and passages. Gentle to moderate winds out of the east to east-
southeast continue to generate some choppy conditions across the
waters as well. Because of this, there is the potential for some
confused seas for the Atlantic waters and passages. Seas will be
generally 5 feet or less, except for the offshore Atlantic, where
seas of up to 6 feet are possible.

There is a moderate risk of rip currents for beaches of Culebra, St.
Croix, St. Thomas, and northern Puerto Rico, including Fajardo, as
well as Aguada and Rincon.

&&

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

$$

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

#21011 Postby cycloneye » Tue Nov 15, 2022 4:33 am

Area Forecast Discussion
National Weather Service San Juan PR
527 AM AST Tue Nov 15 2022


.SYNOPSIS...

Continuing shower activity is likely into the morning. Showers and
isolated thunderstorms have persisted over the waters, pushing
onshore in eastern portions of the region through the night. Active
weather is expected this afternoon, as well, especially affecting
interior and western into northwestern Puerto Rico, with additional
activity in the east associated with streamer development. A drying
trend is expected for midweek into the weekend.

&&

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

A core of moisture with greater than 1.9 inches of precipitable
water is over the forecast area. This will continue to move
westward, with bands of drier and wetter air following in flow
that will gradually turn more easterly and east-northeasterly
during the period. This will lead to a gradual diminution of
showers and thunderstorms across the area on Wednesday and
Thursday, as moisture reaches its lowest point, with precipitable
water of 1.25 inches on Wednesday and then recovers a little on
Thursday. Surface high pressure over the Central Atlantic will be
replaced from the north with another high, but the ridge to our
north will remain. Trade wind flow is expected to increase across
the local areas.

At upper levels, shower activity overnight was aided considerably by
the passage over the area of a trough around the west side of the
TUTT northeast of the area. Flow will then continue from the north
while high pressure remains over the southwest Caribbean, and
this will be consistent with the reduction of activity over the
area tonight through Thursday. The TUTT itself will move little
during the period.

&&

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

Forecast has not changed significantly over the last 24 hours for
the long term, and neither has the reasoning. Still expecting patchy
moisture across the region into the weekend. Precipitable water
values are forecast to be below normal on Friday. On Saturday, a
patch of increased moisture is expected to breeze through the
region, followed by even drier air. Sunday brings more patchy
moisture, with a gradual increase through the day, with more of an
increase later in the day. During this time, an upper-level low is
forecast to push southwestward; this strong TUTT will induce troughs
in the mid-levels and lower levels, as well. On Sunday, this feature
is forecast to be east of the Windward Islands. Overall, expecting a
typical shower pattern, but with inhibited activity. The driest day
could be either Friday or Saturday, depending on the timing of the
patchy moisture. A modest trend towards more active conditions is
expected for Sunday.

Monday and Tuesday bring more active conditions to the region. The
deep-layer trough is forecast to move into the Caribbean on Monday,
and be south of the local islands starting during the day on
Tuesday. This will bring instability to the region, supporting an
increase in convection. Meanwhile, the surface trough, located a
little west of the upper-level feature, will help to drag additional
moisture into the area. Moisture will increase across the islands
through the early part of the next workweek. As a result of this
increased moisture and instability, more shower activity is also
anticipated, remaining in a seasonally typical pattern.

&&

.AVIATION...
(06Z TAFS)

Sct-nmrs +SHRA and isold TSRA will continue across SE PR, the
USVI and adjacent waters with MVFR/IFR conds and mtn obscurations
in ern PR thru at least 15/15Z. These conds will spread across PR
aft 15/16Z. Sfc winds 10-20 kt with hir gusts nr SHRA/TSRA. Max
winds NW 20-30 kt btwn FL420-480.

&&

.MARINE...

There are moderate to locally fresh winds expected across the local
waters, resulting in some choppy conditions. Seas of up to 6 feet
are anticipated across the waters. There is a low to moderate risk
of rip currents across the local beaches. By tonight, a moderate
risk is expected for beaches of the U.S. Virgin Islands, Vieques,
Culebra, and most beaches of Puerto Rico, except south central and
southwestern areas.

&&

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

$$

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

#21012 Postby cycloneye » Wed Nov 16, 2022 4:46 am

Area Forecast Discussion
National Weather Service San Juan PR
453 AM AST Wed Nov 16 2022

.SYNOPSIS...

Patchy moisture will affect the islands over the next several
days, helping to sustain a fairly typical shower pattern. There
will be a gradual increase in shower activity across the region
late Sunday into Monday, with enhanced shower activity for
Tuesday.

&&

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

Moisture drawn up from the moist pool, generally south of 12
degrees north, behind the weak wave that passed through the area
yesterday, is now seen over the Caribbean Sea just south of the
Dominican Republic. Drier air is entering the forecast area
currently, and the driest air is seen over the Leeward Islands.
Nevertheless another patch of moisture is moving toward the area
from just east of 60 W near 20 N, and should arrive later
tonight. Flow at lower levels has turned east northeast and should
remain so until early Thursday morning until high pressure
increases in the Central North Atlantic Ocean when it will become
more easterly. Although precipitable water bottoms out late this
afternoon, it recovers quickly to normal levels by midnight.
Moisture then fades on Friday. Expect precipitable water to vary
between 1.3 and 1.8 inches during the period as described above.

At upper levels high pressure continues across the southwest and
central Caribbean and winds over the local area remains north
northwest to north the entire period. Therefore convection will
mostly be due to variations in the moisture and local effects at the
surface and vary diurnally in the normal manner, with isolated to
scattered showers in eastern Puerto Rico and around the U.S. Virgin
Islands during the late night and early morning hours and afternoon
convection in the western and interior portions of Puerto Rico.

&&

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

Lingering moisture is expected over the region on Monday morning,
though with a dry slot pushing into the area in the east. During the
afternoon, this dry slot is expected to be over the islands, which
will result in a decrease in afternoon convection. Still, what
moisture is available will likely combine with local effects and
daytime heating to result in some showers. Though a thunderstorm or
two cannot be ruled out, the lack of moisture is poised to prevent
more widespread activity.

Patchy moisture returns behind the dry slot late on Saturday. Near-
normal moisture levels are anticipated in the patchy moisture that
will continue through the day on Sunday. Sunday night, an increase
in moisture is expected. This is associated with an induced trough
that will be approaching the region. This increase in moisture will
continue through Monday and into Tuesday. Aloft, an upper-level
trough is forecast to be just east of the Windwards late on Sunday,
moving westward into the southeastern Caribbean by Tuesday. It is
worth noting here that model guidance has backed off on the impacts
of this feature over the region with the most recent model runs,
with the low staying further south of the islands. Because of this,
there is less certainty in the forecast for Tuesday and Wednesday
next week. Despite the changes in model guidance, for which there is
agreement between the Euro and the GFS, an induced trough is still
likely to affect the region on Tuesday, with questions pertaining to
the magnitude of impacts. Instability is expected to increase on
Tuesday, and with moisture above seasonal normals, a marked increase
in shower and thunderstorm activity is likely.

On Wednesday, the influence of the troughing aloft is likely to
weaken, resulting in a decrease in instability over the area.
Meanwhile, drier air is forecast to erode some of the moisture over
the region. Still, moisture will linger over the Caribbean, and may
also linger over portions of the islands. As such, for now the
forecast is for a modest decrease in activity. That there will be a
decrease seems reasonably likely, but it is, yet again, a question
of magnitude, and there is the potential that this forecast is too
wet on Wednesday.

Overall, expect drier weather to persist this weekend, though with a
gradual increase in shower activity behind the passage of the dry
slot on Saturday. This gradual increase is expected to continue
through Monday, with a significant influx in moisture expected for
Tuesday. The typical shower pattern will likely be maintained on
Tuesday, but enhanced shower activity is anticipated. Decreasing
activity is expected for Wednesday.

&&

.AVIATION...
(06Z TAFS)

Little SHRA activity before 16/12Z then SHRA bcmg sct ern PR and
sprdg to wrn PR by 16/17Z. Sct SHRA/isold TSRA til 16/22Z. VFR
conds prevail xcp in SHRA where MVFR and mtn obscuration occur.
Sfc winds bcmg E 8-16 kts with sea breeze influences. Max winds
WNW 30-35 kt btwn FL470-530 and E 18-21 kts btwn FL012-053.

&&

.MARINE...

Moderate to locally fresh winds are expected to continue out of the
east, with speeds of up to 20 knots possible, mostly for the
offshore Caribbean waters and Mona Passage; winds will be generally
up to around 15 knots elsewhere. Isolated to scattered showers are
expected across the waters, and isolated thunderstorms are possible
near the west coast of Puerto Rico each afternoon. Seas will remain
generally 5 feet or less. There is a moderate risk of rip currents
for most beaches of Puerto Rico and the USVI, with the exception of
south central and southwest Puerto Rico.

&&

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

$$

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

#21013 Postby cycloneye » Thu Nov 17, 2022 4:40 am

Area Forecast Discussion
National Weather Service San Juan PR
526 AM AST Thu Nov 17 2022


.SYNOPSIS...
Issued at 446 AM AST Thu Nov 17 2022

Increasing moisture will lead to numerous showers in a typical
pattern across the area. An approaching tropical wave and the
passage of an upper level low to our southeast will bring more
significant rainfall activity beginning Monday of next week.

&&

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

Moisture has increased over much of the region through the night,
resulting in widespread showers over the waters--mostly the
Atlantic waters. Moisture levels have remained generally low for
the Caribbean and, to a lesser extent, St. Croix. Still, a few
showers have occurred there. This shower activity will continue
this morning. This afternoon will bring a typical shower pattern,
which, under the continuing effects of this wetter airmass, is
likely to be increased in extent and strength compared to
yesterday. Showers and isolated thunderstorms will be seen for
interior and western into southwestern Puerto Rico under east-
northeasterly flow; stronger showers are more likely to drift
southward into southwestern Puerto Rico, as there is an increasing
northerly component to the winds, especially above around 25k
feet.

Drying is expected tonight, though some patchy moisture will
continue to stream across the region from time to times, helping to
maintain a typical shower pattern. This drying trend will continue
through much of the day Friday, inhibiting shower development.
Moisture below seasonal normals will likely be over the islands,
especially Puerto Rico, during the afternoon tomorrow; if moisture
is able to linger a little longer, there may be a little more
activity in western and southwestern Puerto Rico than is currently
anticipated.

Patchy moisture will increase late Friday into the night. A large
patch of moisture is expected to affect the islands tomorrow
evening into the night. This will help to sustain passing shower
activity over the waters, of which some will make their way
onshore in windward portions of the islands - the eastern and
northeastern areas. Behind it is more dry air, though, which is
likely to affect the USVI and eastern Puerto Rico by early
afternoon on Saturday, and western Puerto Rico by late afternoon.
Streamer activity in the east is likely to be inhibited, but not
halted, by this drier airmass. In the west, increased afternoon
convection is likely, mostly during the early- to mid-afternoon.
Saturday night is likely to bring a return of patchy moisture,
with near-normal moisture levels in the patches. As such, gradual
increases in shower activity are likely.

Overall, the pattern is for more activity today than yesterday,
affecting interior and western into southwestern Puerto Rico. Friday
brings drier air and a marked decrease in shower activity. A modest
increase in shower activity is anticipated for Friday night into
Saturday.

&&

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

By Sunday a tropical wave will cross through the Windward Islands
and low level flow will turn to the east northeast. Showers will
begin to favor the northeastern side of Puerto Rico and will
increase over the eastern half of the forecast area during the
day. Moisture increases through midnight on Tuesday morning which
will generate showers with significant rainfall for the eastern
third of Puerto Rico during the overnight hours on Monday.
Afternoon showers over western Puerto Rico will also increase
Sunday and Monday. Showers will be more widespread on Tuesday.
But, currently the GFS has a dry slot moving through the area
during the day on Tuesday at 700 mb and there will be a
considerable dip in the precipitable water. This will recover
rapidly overnight and into Wednesday when the best precipitable
water (up to 2.4 inches) is expected to be seen. The flow pattern
and considerable moisture will increase the risk of flooding
Monday through Wednesday and Thursday with the heaviest rain
expected on the southeast side of Puerto Rico. The U.S. Virgin
Islands should see more welcome rain amounts. Low level flow will
be most southeasterly Wednesday night but will continue with a
southerly component through the remainder of the week.

At upper levels a TUTT low will be found east of the Leeward
Islands some 860 miles east southeast of San Juan on Sunday
morning. This will slide southwest to the coast of Venezuela by
Wednesday morning. During this transit it will be wrapped with a
50 knot jet along its northwest side that will approach the local
area on Monday. A weak trough will also cross through the area
that will induce mid level troughing to our east and bring cooler
temperatures to the 500 mb level beginning Monday that will enhance
the shower generation created by the wind surge and troughing
Tuesday and Wednesday in lower levels.

&&

.AVIATION...
(06Z TAFS)
Issued at 446 AM AST Thu Nov 17 2022

Generally VFR conds expected next 24 hours for most terminals, but
cannot rule out brief MVFR due to SHRA for TIST/TJSJ/TJBQ before
17/14Z. Afternoon activity interior and W into SW PR. SHRA/TSRA
expected to remain N and W of TJPS, and S of TJBQ. Winds pick up
after sunrise, generally ENE at 10 to 15 knots, with sea breeze
variations. Winds diminish after sunset, to 4 to 8 knots
overnight.

&&

.MARINE...
Issued at 446 AM AST Thu Nov 17 2022

Winds are increasing over the local outer Atlantic waters and will
cause choppy conditions to persist. Small craft will need to
exercise caution there. Seas may become hazardous early next week
in both the Atlantic and Caribbean local outer waters. Weather conditions
will deteriorate Monday through Wednesday with areas of heavy rain
and isolated thunderstorms when a tropical wave approaches and
moves through the area.

&&

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

$$

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

#21014 Postby cycloneye » Sat Nov 19, 2022 5:27 am

Area Forecast Discussion
National Weather Service San Juan PR
502 AM AST Sat Nov 19 2022


.SYNOPSIS...Passing showers are expected to continue across the US
Virgin Islands and eastern Puerto Rico during the morning hours. Shower
activity is expected across the Central Cordillera and southwestern
portions of Puerto Rico later today. Then, expect a surge of low-
level moisture moving over the islands late in the afternoon
hours. Choppy marine conditions persist, and a moderate risk of
rip currents remain in effect across most of the beaches of the
islands.


&&

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

Trade wind showers were observed overnight across the regional
waters, with some of them moving at times across the islands. The
doppler radar estimated near half an inch of rain between Yabucoa
and Humacao. The GOES-16 Total Precipitable Water(TPW) is showing an
area of max TPW of 1.50 inches moving over the northern U.S. Virgin
Islands. This area extends from the Anegada Passage into eastern
Puerto Rico. Trailing this surge of low-level moisture there is
another broad area with a TPW minimum of 0.98 in., which is expected
to move over the islands later this afternoon, promoting fair
weather conditions and sunny skies. Having said that, the first band
of higher TPW will continue to promote trade wind shower activity
across the USVI and eastern sections of PR during the morning hours,
and it should be enough to trigger diurnal shower activity over
portions of southwestern PR this afternoon.

A TUTT induced surface trough over the central Tropical Atlantic is
expected to move across the region from late Sunday into Monday.
Precipitable water content is expected to peak near 2.00 inches on
Monday afternoon. Showers with possible isolated thunderstorms are
expected to increase in coverage across the regional waters and all
the islands. Therefore, there will be an elevated urban and small
stream flooding threat across PR and the USVI during this period.
Breezy conditions are expected as well, as low-level trades prevail
between 20-25 kt.

&&

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

A low level trough and a tropical wave across the local area are
forecasted to bring more showers and isolated thunderstorms across
the local area until at least Tuesday. Precipitable Water Content
(PWAT) values will range between 1.70 to 2.12 inches which
indicate a moisture pattern will continue across the area, just
ahead of another tropical wave on late Wednesday and continuing
until Friday night. This wave is expected to cross the area,
leaving showers and thunderstorms across most of the islands.
Although, we can expect an increase in moisture content there is
high uncertainty of the expected amounts of rain and its possible
impacts. However, soils continue saturated across much of the area
and the risk for mudslides and flooding are present. The eastern
portions of Puerto Rico and the US Virgin Islands should expect
the rainfall activity during the morning hours, followed by the
afternoon convection across the Central Cordillera and western
portions of Puerto Rico. Conditions will slowly start to improve
by Friday afternoon into Saturday morning. A high surface pressure
will establish and drier air will filter into the region. Expect
mainly fair weather conditions with those heat indices reaching
the upper 90s and lower 100s across the northern portions of
Puerto Rico.

&&

.AVIATION....Mainly VFR conditions are expected to prevail across
all terminals through the forecast period. However, trade winds
showers could move at times through the morning hours across the
USVI and eastern PR terminals. East to northeast winds will increase
between 12-18 kt with higher gusts and sea breeze variations aft
14z.


&&

.MARINE...Moderate to fresh easterly winds between 15 to 20 kts
will prevail for the next several days and will promote choppy
marine conditions over the local waters. Seas will remain between
4 to 6 feet across most of the waters. A northerly swell will
continue through the weekend. Therefore, small craft should
exercise caution. There is a moderate risk of rip currents in
effect for all the coast of the islands, except for the southern
coast of Puerto Rico.

&&

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

$$

DSR/GRS
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Re: Caribbean - Central America Weather

#21015 Postby cycloneye » Sun Nov 20, 2022 5:08 am

Area Forecast Discussion
National Weather Service San Juan PR
447 AM AST Sun Nov 20 2022


.SYNOPSIS...Showers will continue across the US Virgin Islands
and eastern Puerto Rico during the morning hours. Later in the
afternoon hours, the activity will concentrate over the
southwestern quadrant of Puerto Rico. A surge of low- level
moisture will move over the islands later today into Monday.
Seas will remain choppy across the local waters for the next
several days.

&&

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

Showers and low-level clouds embedded in the trade winds will
continue to move from time to time across the regional waters, and
across the U.S. Virgin Islands and Puerto Rico. This will promote
sunny to partly cloudy skies through the day, with periods of
moderate to brief heavy rainfall over the islands. However, the
local area remains under the influence of drier air at the mid-
levels, promoted by a ridge to our north. This ridge will also keep
warmer than normal 500 mb temperatures, and suppress thunderstorm
activity this afternoon across western PR with the typical diurnal
shower development.

Having said that, weather conditions are expected to change
gradually tonight into Monday, as moisture content increases from
the east, as a TUTT induced surface trough over the central Tropical
Atlantic is expected to move across the eastern Caribbean.
Precipitable water content is expected to peak near 2.00 inches by
Monday afternoon. Showers with possible isolated thunderstorms are
expected to increase in coverage across the regional waters and all
the islands. Therefore, there will be an elevated urban and small
stream flooding threat across PR and the USVI during this period.
Breezy conditions will prevail with 20-25 kt low-level trades. A
quick drying trend is expected on Tuesday, but a trade wind shower
pattern will return once again, and similar conditions as today are
expected.

&&

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

A tropical wave is forecasted to cross the islands. This wave will
bring another round heavy showers and isolated thunderstorms across
the local area. Associated moisture will reach the eastern portions
of Puerto Rico and the US Virgin Islands by Wednesday through
Friday. Citizens of the local islands should expect the rainfall
activity during the morning hours, followed by the afternoon
convection across the Central Cordillera and western portions of
Puerto Rico. The Precipitable Water Content (PWAT) values are
expected to range between 1.82 to 2.00 inches. Soils continue
saturated across much of the area and the risk for mudslides and
flooding will be present. Nonetheless, drier air will start to
filter into the local area and a more stable weather pattern will
settle. Overall, conditions will improve starting on Saturday and
fair weather conditions will be seen across much of the area. This
pattern will remain for the weekend. By late Sunday onwards,
another tropical wave is expected to bring more moisture and
unstable weather conditions will return. Expect heat indices
reaching the upper 90s and lower 100s across the northern portions
of Puerto Rico everyday.

&&

.AVIATION....Mainly VFR conditions are expected to prevail across
all terminals through the forecast period. However, trade wind
showers could move at times across TIST/TISX/TJSJ/TJBQ, which could
cause BKN cigs btw FL025-FL050. E-ENE winds will increase between 12
and 18 kts with higher gusts aft 20/14z.

&&

.MARINE...Moderate to fresh easterly winds between 15 to 20 kts
continue to promote choppy marine conditions over most of the
local waters. Therefore, small craft should exercise caution while
navigating. Seas will remain between 4 to 6 feet across most of
the waters. A northerly swell will continue through the weekend. There
is a moderate risk of rip currents in effect for the majority of
the local beaches of the islands, except for the southern coast
of Puerto Rico.


&&

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

$$

DSR/GRS
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Re: Caribbean - Central America Weather

#21016 Postby cycloneye » Mon Nov 21, 2022 4:49 am

Area Forecast Discussion
National Weather Service San Juan PR
519 AM AST Mon Nov 21 2022

.SYNOPSIS...Trade wind showers will continue to affect our area
during the morning hours. A TUTT surface induce trough continues
to approach the local area and a increase in showers and isolated
thunderstorms is expected across the islands. These will cause urban
and small stream flooding in susceptible areas. Marine conditions
will also deteriorate, becoming choppy and hazardous across the
regional waters.

&&

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

Trade wind showers were observed overnight across the regional
waters, with some of them moving at times across the islands.
However, the doppler radar estimated minor rainfall amounts over
land areas. Meanwhile, a TUTT induced surface trough is approaching
the Lesser Antilles, and the GOES-16 Total Precipitable Water (TPW)
is showing a broad area of TPW of 2.00 inches that is expected to
reach the region later today and through early Tuesday morning. This
surge in moisture and increased instability will promote shower and
thunderstorm development across the regional waters and all the
islands. Therefore, there will be an elevated threat of urban and
small stream flooding, particularly across the eastern half of
Puerto Rico. In addition, a wind surge will maintain breezy
conditions as trade winds peak between 20-25 kt. A quick drying
trend is expected on Tuesday, but a trade wind shower pattern will
return once again later in the day. Another showery day is
expected on Wednesday with the passage of an easterly wave across
the eastern Caribbean.

&&

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

A passing tropical wave is forecasted to move over the local area by
Thursday into Friday. This forecast continue on track and have not
changed in the last 24 hours. This wave is expected to generate
showers and thunderstorms activity across much of the region. Due to
the continuous rains from the previous weeks, soils continue very
saturated across the area. Be aware of the main potential hazards
which includes: excessive rainfall, flooding, mudslides and high
winds. The Precipitable Water Content (PWAT) values up to 2.00
inches indicates an enhancement of moisture that will result in
the expected activity. By Friday conditions will start to slowly
improve as the wave move west of the area, but its associated
moisture will continue to linger and will enhance more showers
across the islands. However, by Saturday through Sunday a more
seasonal weather will establish and fair weather conditions will
return to our area. The eastern portions of Puerto Rico and the US
Virgin Islands will expect some passing showers across the
morning hours, then the southwestern portions of Puerto Rico will
see some activity due to the diurnal heating and local effects.
The latest GFS model guidance suggest the approaching of a second
tropical wave by Monday, this wave will bring another round of
moisture across the islands. This wave is expected to move fast,
but some unstable weather conditions will be seen. Across the
area, heat indices will reaching the upper 90s and lower 100s
across the northern portions of Puerto Rico each day.

&&

.AVIATION....Mainly VFR conditions are expected to prevail
early in the forecast period. Passing SHRA could move at times
across TIST/TISX/TJSJ/TJBQ, which could cause BKN cigs btw FL025-
FL050. Later this afternoon and through the night, SHRA/TSRA should
increase from the east and in diurnal convection. This may lead to
tempo MVFR conditions across most terminals. East winds will
increase between 12 and 18 kts with higher gusts aft 21/14z.

&&

.MARINE...Moderate to fresh easterly winds between 15 to 20 kts
with higher gusts will continue to promote choppy conditions
across the local waters. Seas between 5 to 7 feet are expected
across offshore Atlantic Waters and the offshore Caribbean
waters and passages.


Marine and coastal conditions will deteriorate today and until the
end of the work week, becoming hazardous across the local waters
and passages. Please refer to the latest Coastal Waters Forecast
(CWFSJU) and the latest Marine Weather Message (MWWSJU) issued by
WFO San Juan PR for more information on the Small Craft Advisories
that will be in effect from tomorrow afternoon.

A high risk of rip currents is currently in effect for the eastern
beaches of Saint Croix. Then, later today more local beaches
across the islands will be under a high risk as well.


&&

.SJU WATCHES/WARNINGS/ADVISORIES...
PR...High Rip Current Risk from this evening through Wednesday
afternoon for PRZ001-002-012.

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

&&

$$

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

#21017 Postby cycloneye » Tue Nov 22, 2022 4:40 am

Area Forecast Discussion
National Weather Service San Juan PR
440 AM AST Tue Nov 22 2022


.SYNOPSIS...Breezy conditions are expected across the islands
today. Drier air filtering into the region will promote fair
weather conditions and limited shower activity. Overnight,
moisture associated to a tropical wave south of the area will
increase. Expect showers across the area from time to time.
Choppy and hazardous marine conditions continue across the
regional waters.

&&

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

The area will remain under the influence of an upper level trough to
our east and a ridge to the west through the short term period.
Breezy conditions will continue today across the region. Drier air
is moving in from the east, and precipitable water content is
expected to range from 0.80-1.00 inches through this afternoon. This
will promote fair weather conditions across the islands, and mostly
sunny skies with limited shower development over land areas this
afternoon. Maximum temperatures should range from the upper 80s to
low 90s across coastal areas, but the heat index should remain below
100F.

Moisture content is expected to gradually increase this evening into
the overnight hours as an easterly wave moves across the eastern
Caribbean, well to our south. This surge in moisture will increase
PWAT values between 1.70-1.90 inches through Wednesday afternoon.
Therefore, trade wind showers will increase across the USVI and
eastern half of PR through the morning hours, followed by diurnally
induced afternoon convection over portions of the interior and
western PR. Urban and small stream flooding is expected with this
activity in PR. Another surge in low-level moisture is expected
between 24/00z-10z from the Anegada Passage, increasing shallow
nighttime convection between the USVI and eastern PR once again.
Diurnally induced afternoon convection is expected across
west/southwest PR, where the threat of urban and small stream
flooding will remain elevated.

&&

LONG TERM...Friday through Wednesday...

Moisture associated to a tropical wave, west of the region, will
continue to induce showers across the islands. However, as this wave
continues to move away from our area the weather conditions will
slowly improve over the day and more stable conditions will be
observed. Over the weekend, a seasonal weather pattern is expected
to establish and fair weather conditions under mostly partly clody
skies will return to our area. The eastern portions of Puerto Rico
and the US Virgin Islands will expect some passing showers across
the morning hours, then the southwestern portions of Puerto Rico can
expect some convection due to local effects and daytime heating. The
general wind flow from the east to northeast will prevail for
several days. Pleasant temperatures are expected over portions over
the Central Cordillera. By early Monday, a weak tropical wave will
pass south of the local area but no significant impacts are expected
at the time. For the rest of the long-term forecast, a mostly
advective pattern will prevail across the islands. Showers from time
to time will affect portions of the US Virgin Islands and Puerto
Rico. Heat indices will reach the upper 90s across the northern
portions of Puerto Rico each day.


&&

.AVIATION....Mainly VFR conditions are expected to prevail across
all terminals during the next 24 hours. E-ENE winds at 12-16 kts
with higher gusts aft 21/14z.

&&

.MARINE...Winds will continue to increase over the local area,
causing choppy and hazardous seas, increasing up to 8 feet. These
conditions will continue through at least mid-week. Please refer to
the latest Coastal Waters Forecast (CWFSJU) and the latest Marine
Weather Message (MWWSJU) issued by WFO San Juan PR for more
information on the Small Craft Advisories. For beachgoers, there
is a high risk of rip currents for the northern coast of Puerto
Rico, Culebra and Saint Croix.


&&

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

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

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

&&

$$

DSR/GRS
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Re: Caribbean - Central America Weather

#21018 Postby cycloneye » Thu Nov 24, 2022 6:22 am

Area Forecast Discussion
National Weather Service San Juan PR
514 AM AST Thu Nov 24 2022


.SYNOPSIS...Happy Thanksgiving... Approaching drier air should
limit advective trade wind shower activity over the local islands
during the morning hours. Convective development is still expected
across the interior and western municipalities during the
afternoon hours. A patch of moisture should move in late tonight
and into Friday before a drier pattern starts to dominate during
the weekend. A northerly swell will reach the local waters early
next week, further deteriorating marine conditions.

There is a moderate risk of rip currents for the northwestern,
northern, eastern and southeastern beaches of Puerto Rico, along
with all of the beaches of Vieques, Culebra, and the USVI. Life-
threatening rip currents often occur in the vicinity of groins,
jetties, reefs, and piers.

&&

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

The most recent satellite imagery shows an enhanced area of moisture
currently located just south of the local islands, with a slot of
drier air gradually approaching the Virgin Islands. At the mid and
upper levels, a ridge continues to hold, hence all the moisture is
confined below 500 mb. The trade winds will maintain an advective
pattern across the U.S. Virgin Islands and eastern Puerto Rico each
day. However, the winds are still in the moderate side, with a
steering flow around 13 knots, and flooding rains are not expected
with this activity. In the afternoon, the high resolution guidance
also show the development of additional showers across the interior
and western Puerto Rico. Late on Thursday and early Friday, another
patch of moisture moved in, with precipitable water values climbing
around 1.8 inches, which is above the climatological mean for this
time of year. Therefore, expect brief but frequent showers in the
same areas, causing wet roads and ponding of water in low-lying
areas. The pattern begins to shift by early in the weekend, with a
little drier air mass above 850 mb. However, under a northeasterly
wind flow, shallow showers tend to form just north of the islands,
affecting the windward areas at times.

&&

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

Generally fair weather conditions, along with the seasonal
weather pattern, are expected to prevail for most of the long term
period. Ridging is expected to continue for most of the week,
along with generally drier air with relatively more humid air
patches with slightly below normal to normal moisture. Mainly
northeasterly winds are expected to prevail for most of the long
term period. Under these northeasterly winds, heat indices will
reach the upper 90s across the northern portions of Puerto Rico
each afternoon. The seasonal weather pattern includes showers
advecting into sectors of northeastern and eastern forecast area
during the morning hours and limited convective development during
the afternoon hours, due to diurnal and local effects, mainly
affecting western and southwestern municipalities. Showers should
be limited, as the ridge and associated dry air above 850 mb
inhibit development. Increases in rain chances will depend on
patches of generally more humid air affecting the area. Current
model guidance shows areas with precipitable water values of
between 1.5 and around 1.7 inches, remnants of a frontal boundary
reaching the area under the northeasterly flow early next week.
The frequency of more humid air masses filtering into the region
increases by midweek, increasing shower activity. With the ridge
continuing to hold and TUTT developing but staying far east of our
region, unfavorable conditions will continue to limit convective
development through Friday.

&&

.AVIATION...Mainly VFR conditions expected to prevail through the
forecast period. VCSH will affect all the local terminals, with
possible brief periods of low ceilings and reduced VIS. SHRA are
expected after 17Z for the Cordillera Central with mountain
obscuration expected. Wind will pick up after 14Z, coming out of
the east at around 12 to 16 knots with stronger gusts.

&&

.MARINE...
Moderate to locally fresh easterly winds will persist, causing
choppy conditions across areas of the local waters and passages.
Seas will remain choppy through the weekend, especially across the
offshore waters. Passing showers will continue to affect the
local waters for the next several days. A northerly swell will
reach the local waters early next week, deteriorating marine
conditions.

A Small Craft Advisory is in effect for the offshore Atlantic
waters until early this morning. Nevertheless, small craft should
exercise caution over the offshore Caribbean Waters, the Mona
Passage and the Atlantic waters.

The risk of rip currents is now moderate for the northwestern,
northern, eastern and southeastern beaches of Puerto Rico, along
with all of the beaches of Vieques, Culebra, and the USVI. Life-
threatening rip currents often occur in the vicinity of groins,
jetties, reefs, and piers.


&&

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

$$

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

#21019 Postby cycloneye » Fri Nov 25, 2022 7:55 am

Area Forecast Discussion
National Weather Service San Juan PR
420 AM AST Fri Nov 25 2022

.SYNOPSIS...

A patch of moisture will promote passing showers that will
continue to mainly affect eastern Puerto Rico but no significant
rainfall accumulation is expected. Nevertheless, showers should
affect the west in the afternoon. On Saturday, mainly fair weather
will prevail. On Sunday, light to moderate convective activity in
the west should again develop during the afternoon hours. A
seasonal weather pattern under a more northeasterly flow and
patches of moisture from time to time is expected to prevail
during the workweek.

There is a moderate risk of rip currents for the northwestern,
northern, eastern and some southeastern beaches of Puerto Rico,
along with most of the beaches of Vieques, Culebra, and the USVI.
Life-threatening rip currents often occur in the vicinity of
groins, jetties, reefs, and piers.

&&

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

The forecast remains on track for the last weekend of November. A
mid to upper level ridge continues to hold over the western
Caribbean, maintaining dry air aloft. This trend has been confirmed
by the TJSJ 25/00Z sounding that had relatives humidities below 10%
above 13000 feet (650 mb). At the surface, a high pressure just
north of the Greater Antilles will maintain trade winds coming out
of the east at 10 to 15 knots, and the winds will relax a little by
the end of the weekend as this high weakens. The shower activity
will depend on patches of moisture dragged at times by the wind,
mainly affecting eastern Puerto Rico and the United States Virgin
Islands. This advective pattern is seasonal, with convection
activity in the afternoon for western Puerto Rico gradually tapering
off.

For today, one of the aforementioned patches of moisture will
arrive, causing some passing shower activity, but no significant
rainfall accumulation is expected. On Saturday, the GFS shows
dewpoint depressions of 20 to 25 degrees Celsius, which means that
mainly fair weather conditions should prevail. Then on Sunday,
another small pocket of enhanced moisture arrives, with
precipitable water values climbing to around 1.6 inches (near
normal). A few more showers can be expected at times for eastern
PR/USVI, followed by light to moderate convective activity in the
west in the afternoon hours.

&&

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

No major changes to the long term forecast since the last
discussion. Ridging is expected to continue to dominate for most of
the long term forecast period. In addition, generally dry air will
dominate with the exception of more humid patches of air, with
slightly below normal to normal moisture, reaching our region from
time to time under northeasterly winds. Any available moisture
however, will remain below around 850 mb as the mid and upper levels
will be dry, this will also serve to inhibit shower development.
Mainly fair weather conditions, along with the seasonal weather
pattern, are still expected to prevail. With the seasonal weather
pattern and northeasterly winds, showers are expected to advect into
sectors of the northern and eastern forecast area during the morning
hours and limited convective development is expected to affect
mainly western and southwestern Puerto Rico during the afternoon
hours, due to diurnal and local effects. Under the northeasterly
winds that are expected to prevail throughout the long term
forecast period, heat indices will reach the upper 90s, especially
across the northern portions of Puerto Rico each afternoon. A
TUTT will develop over the eastern atlantic but will stay far east
of our region, and not affect us directly. Increases in rain
chances will depend on the patches of relatively more humid air
that will affect the area. Current model guidance shows areas with
precipitable water values of between 1.5 to around 1.7 inches,
remnants of a frontal boundary, reaching the area. A weak tropical
wave will also move south of our region early next week, but the
bulk of moisture will remain outside our region. The frequency of
patches of more humid air filtering into the region increases by
midweek and lulls on Friday and into the weekend. Late on
Saturday, it is possible that an upper level low pressure system
will approach the area, increasing instability and rain chances.

&&

.AVIATION...Mainly VFR conditions expected to prevail. A few SHRA
are expected across the area, but with very limited impacts to
operation. SHRA could develop after 17Z over the western half of
the Cordillera Central, causing mountain obscuration. Winds will
pick up after 14Z, out of the east at 12 to 13 knots, with
stronger gusts.

&&

.MARINE...

Moderate easterly winds will continue to promote choppy conditions
across areas of the local waters and passages. Small craft
operators should exercise caution over the offshore Atlantic
waters where seas are up to 6 ft. Seas of 5 ft or less elsewhere.
Passing showers will continue to affect the local waters for the
next several days. A drying trend will begin Saturday. Seas in
northerly swell will increase again Monday and Monday night.

There is a moderate risk of rip currents for the northwestern,
northern, eastern and some southeastern beaches of Puerto Rico,
along with most of the beaches of Vieques, Culebra, and the USVI.
Life-threatening rip currents often occur in the vicinity of
groins, jetties, reefs, and piers.

&&

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

$$

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

#21020 Postby cycloneye » Sat Nov 26, 2022 7:00 am

Area Forecast Discussion
National Weather Service San Juan PR
511 AM AST Sat Nov 26 2022

.SYNOPSIS...Generally fair weather and dry conditions should
prevail today with only limited shower activity. A slight increase
in moisture is expected on Sunday and a limited seasonal pattern
is expected throughout the workweek with increases in rain chances
depending on patches of moisture filtering into the region. A
weak tropical wave will reach the U.S. Virgin Islands late Sunday
night or early Monday morning, but the bulk of moisture will
remain south of the region. A long- period northeasterly swell
will deteriorate marine and coastal conditions from early Monday
through at least early Wednesday.

There is a moderate risk of rip currents for the northern beaches
of Puerto Rico, the beaches of Culebra and western beaches of
Vieques and St. Croix. Low risk of rip currents elsewhere. Life-
threatening rip currents often occur in the vicinity of groins,
jetties, reefs, and piers.

&&

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

A mid- to upper-level ridge building aloft will maintain stable
weather conditions. Model guidance indicated moisture confined below
700 MB with a dry air mass above it. Satellite images also detect
low-level moisture (supporting model guidance suggestions) embedded
in the trades with TPW derived from GOES-E ranging between average
and above normal. The ridge pattern will hold throughout the
forecast period. Therefore, we are expecting a mixture of
sunshine/clear skies with the advection of pockets of moisture with
clouds and showers from time to time. In the meantime, a cold front
will move across the Western Atlantic, sinking southward but away
from the northeast Caribbean (local region) today and tomorrow.
Scattered showers will increase, especially at night, because of
cold air advection over the warmer waters. Then, a weak tropical
wave will reach the U.S. Virgin Islands late Sunday night or early
Monday morning, with the bulk of moisture way to the south over the
Caribbean Sea.

A northeasterly long-period swell will create dangerous breaking
waves resulting in life-threatening rip currents along the Atlantic
Coastline of Puerto Rico and the U.S. Virgin Islands around Monday
morning into the afternoon.

&&

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

Mainly fair weather conditions, along with the seasonal weather
pattern, are expected for most of the workweek and next weekend. A
mid- to upper-level ridge will prevail during most of the long
term forecast period. Northeasterly winds will also continue into
the long term period; heat indices up to the upper 90s will be
observed, especially across the northern portions of Puerto Rico
each afternoon. At the surface, relatively dry air will dominate
the region with the exception of humid patches of air, with
slightly below normal to normal precipitable water values,
reaching the local islands from time to time. Most of the
available moisture will remain in the lower levels of the
atmosphere and dry air will prevail in the mid to upper levels,
also limiting shower development. A TUTT will develop over the
eastern Atlantic but will stay far east of our region, not
affecting us directly. These factors will limit any activity, but
with the seasonal weather pattern and northwesterly winds, showers
are expected to advect mainly into the eastern forecast area
during the morning hours and, during the afternoon, limited
convective development due to diurnal and local effects is
expected to affect mainly western and southwestern Puerto Rico.
Increases in rain chances will depend on when the patches of
relatively more humid air that will affect the area. Model
guidance continues to show areas with precipitable water values of
between 1.5 to around 1.7 inches, remnants of a frontal boundary,
reaching the area on Tuesday. Model guidance also shows other
areas of more humid air affecting the region during the overnight
hours on Thursday, on Friday and on Saturday night into Sunday.
Additionally late on Saturday and into Sunday, it is possible that
an upper-level low pressure system will approach the area,
increasing instability and rain chances.

A northeasterly long-period swell will continue to affect the
region through midweek. This swell will result in dangerous
breaking waves that will peak on Tuesday along with life-
threatening rip currents along the Atlantic Coastline of Puerto
Rico and the U.S. Virgin Islands.

&&

.AVIATION...VFR conditions will prevail throughout the forecast
period. However, occasional passing -SHRA/SHRA will affect
TJSJ/IST/ISX. SHRA will develop over the Cordillera Central and
may impact JPS in the afternoon (btwn 26/17-22z). Winds will
continue calm- light/VRB thru 26/13z, returning from the ENE at
10-15 kt afterward with higher gusts and sea breeze variations.

&&

.MARINE...Moderate easterly winds will persist, causing a
moderate chop across most of the local waters and passages for the
next few days. For today, expect seas up to 5 feet for the local
Atlantic Waters and seas of 4 feet or less elsewhere. Passing
showers will continue to affect the local waters, though fewer are
expected through at least early next week. A weak tropical wave
will move across the northeastern Caribbean by Monday and a long-
period northeasterly swell will deteriorate marine and coastal
conditions from early Monday through at least early Wednesday.

There is a moderate risk of rip currents for the northern beaches
of Puerto Rico, the beaches of Culebra and western beaches of
Vieques and St. Croix. Low risk of rip currents elsewhere. Life-
threatening rip currents often occur in the vicinity of groins,
jetties, reefs, and piers.

&&

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

$$

SHORT TERM...CAM
LONG TERM....MRR
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