Caribbean - Central America Weather

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cycloneye
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Re: Caribbean - Central America Weather

#19581 Postby cycloneye » Tue Sep 11, 2018 5:00 am

Area Forecast Discussion...CORRECTED
National Weather Service San Juan PR
555 AM AST Tue Sep 11 2018

.SYNOPSIS...Several minor troughs will move through the area ahead
of Tropical Storm Isaac with afternoon showers and thunderstorms
expected in western and interior Puerto Rico, but only isolated
shower in the U.S. Virgin Islands. Considerable uncertainties
continue with regards to the track and intensity of Isaac, but
present forecasts show it passing south of the forecast area as a
Tropical storm, spreading gusty winds, showers and thunderstorms
across the area. Considerable moisture follows Isaac on Saturday
that will keep the weather wet well into next week.

&&

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

Patches of low level moisture transported by an east to southeast
wind flow will bring light to moderate passing showers over portions
of eastern Puerto Rico and the U.S. Virgin Islands during the
morning hours. Then, the combination of the available moisture with
local and diurnal effects along with favorable upper level
dynamics with the passage of an upper level trough, will favor
the development of showers and thunderstorms, particularly across
interior and western Puerto Rico. Also, streamer-like showers and
thunderstorms are possible over the San Juan metropolitan area.
Urban and small stream flooding is likely with the heaviest
activity. Elsewhere, mostly fair weather conditions expected.

The entrance of an elongated area of a somewhat drier air ahead of
Tropical Cyclone Isaac will result in mostly tranquil weather
conditions across the local area on Wednesday enhanced by the
passage of an upper level ridge. Although limited, the potential
for afternoon convection over portions of the interior and western
Puerto Rico remains. By late Wednesday night into Thursday
morning, Isaac`s forward outer rain band will move across the
local area. This feature will enhance shower and thunderstorms
activity, and will bring gusty conditions across the local islands
and waters. At this time, the intensity and coverage of the
activity, as well as any additional threat or impact this tropical
cyclone could bring to the local area are yet to be determined
given the uncertainties that relates to Isaac`s track and
intensity forecast.

.LONG TERM...Friday through Tuesday...
Although the track and intensity of Tropical Storm Isaac are still
surrounded by uncertainties, the current forecast shows it
passing south of the area Thursday night through Friday night. It
will likely bring seas greater than 8 feet by Wednesday night or
Thursday and seas in the southern part of our Caribbean waters
greater than 15 feet for Friday cannot be ruled out at this time.
Upper level flow between a high to the northwest and a TUTT to
the northeast will be northeast over the area and will contribute
shear that will weaken tropical cyclone Isaac when it arrives on
Friday. After the passage of TC Isaac, moist flow continues
beyond the end of the period with precipitable water forecast to
be above 2 inches after midday on Saturday. During this latter
period many bubbles of divergence aloft pass over the local area
will present an environment favorable to heavy shower activity and
isolated thunderstorms.

Expect that weather will remain wet and that most areas
will have at least some rainfall with local urban and small stream
flooding possible each day. Models do not suggest major/widespread
flooding with the passage of Isaac so far south.

&&

.AVIATION...Mainly VFR conditions expected to prevail across all
terminals during the next 24 hours. However, VCSH expected at TIST,
TISX and TKPK until 11/13Z. Afternoon convection will result in VCTS
across all PR terminals between 11/16Z and 12/00Z with mountain
obscurations and strong sea breeze variations with gusty winds.
This can result in tempo MVFR conditions at TJSJ, TJBQ, TJPS and
TJMZ. Fair weather conditions will return after 12/00Z across all
terminals although some mountain obscurations and scattered
showers will persist overnight in ern PR and around the USVI.

&&

.MARINE...Pulses of swell have been moving through the local outer Atlantic
waters and just beyond from Major Hurricane Florence. This has
mostly resulted in increased rip currents on the north coast of
Puerto Rico. This situation is expected to continue through the
end of the week. Seas from Tropical Storm Isaac will arrive
Wednesday night or Thursday morning should the current forecast
tack and intensity hold. As mentioned above, seas greater than 8
feet are possible by Wednesday night or Thursday and seas in the
southern part of our Caribbean waters greater than 15 feet for
Friday cannot be ruled out at this time. Seas in the Atlantic
will become confused as swell from both Isaac and Florence
combine.

Seas in the Caribbean should fall below 7 feet on
Saturday and seas in the Atlantic should have subsided by Sunday.

&&

.PRELIMINARY POINT TEMPS/POPS...
SJU 87 79 89 79 / 40 10 40 70
STT 91 80 90 80 / 40 40 70 70
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Re: Caribbean - Central America Weather

#19582 Postby cycloneye » Wed Sep 12, 2018 5:04 am

Area Forecast Discussion
National Weather Service San Juan PR
532 AM AST Wed Sep 12 2018

.SYNOPSIS...The proximity of a Tutt low just west of the region
and a plume of moisture in the prevailing east to northeast flow
ahead of Tropical Storm Isaac will support showers and isolated
thunderstorm activity across the coastal waters and parts of the
islands the rest of today. Based on the current forecast track,
Tropical Cyclone Isaac is forecast to move westward and remain
south of Puerto Rico and the U.S. Virgin Islands late Thursday
evening through Friday. A moist and unstable environment will
persist for the next several day and into the upcoming weekend.

&&

.SHORT TERM...Today through Friday...
The entrance of an elongated area of a somewhat drier air ahead of
Tropical Storm Isaac will reach the forecast area early this morning
and will cross the local islands throughout the day. Although this
feature will bring mostly tranquil weather conditions across the
region, streamer-like showers moving over the waters into eastern
Puerto Rico and the U.S. Virgin Islands during the morning hours, as
well as afternoon showers and thunderstorms developing over the
interior and western Puerto Rico remains possible due to the diurnal
effects. Urban and small stream flooding is likely across these areas.

Once this area of drier air continues to move westward and away from
the local islands, weather conditions are expected to deteriorate as
Isaac`s forward outer band streams across the region late Wednesday
night into Thursday. This will feed squally weather conditions along
with gusty winds and frequent lightning activity across the forecast
area as it progress westward. Streamer-like showers and thunderstorms
will move over the waters into land areas early Thursday morning into
Thursday afternoon, then afternoon convection will be triggered over
portions of the interior and western Puerto Rico. A secondary event
is then expected on Friday as Isaac approaches the local area. Although
the storm is expected to remain south of the local islands, showers
and thunderstorms are expected across most of the forecast area. Based
on the current forecast, total rainfall accumulations are forecast
to range between 1 and 3 inches with isolated higher amount`s. Thus,
urban and small stream flooding, rapid rises along rivers, and mudslides
near steep terrain are highly likely during this forecast period.

.LONG TERM...Saturday through Wednesday...
Tropical Storm Isaac is still surrounded by uncertainties as far
as intensity, as it is expected to continue to feel the effects of
westerly and northwesterly shear. However the current forecast
shows it passing south of the U.S.Virgin Islands and Puerto Rico
from Friday through Saturday. It will likely bring seas between 8
to 10 feet at least through Saturday mainly over the southern
portion of the local Caribbean waters and passages. After the
passage of Isaac, a moist southeasterly flow will continue across
the region through most of the upcoming weekend and into early
next week. Recent model guidance continued to suggest layered
precipitable water values in excess of 2 inches into early next
week. This along with the proximity of another Tutt low will
maintain a moist and unstable environment through ahd least Monday
of next week with a gradual improvement by Tuesday. That said,
expect fairly wet weather pattern favorable which will support
periods of moderate to heavy rainfall with showers and isolated
thunderstorm activity most of the period. Local urban and small
stream flooding will remain possible each day with potential for
mudslides in areas of steep terrain. However,model guidance still
do not suggest widespread flooding during the period.

&&

.AVIATION...VFR conditions will prevail across most terminals through
the forecast period. However, MVFR conditions are expected across
the TNCM terminal this afternoon as occasional bands of passing
showers move across the area in the northeasterly wind flow. SHRA/TSRA
are expected to develop across the interior and western portion of
Puerto Rico on Wednesday afternoon for possible impacts across TJMZ.
Surface winds will be from the northeast across all area sites through
the forecast period light up to 8 knots becoming 10 to 15 knots aft
12/14z with sea breeze variations.

&&

.MARINE...Seas up to 6 feet over the Atlantic waters and Caribbean
passages with easterly winds 10 to 20 kts today. Later this evening
and overnight, expect increasing and deteriorating seas up to 8
to 10 feet over the offshore Atlantic and Caribbean waters and
local passages with the approach of Tropical Storm Isaac. Therefore,
a small craft operators are urge to exercise caution today and
small craft advisories will be in effect later this evening.
Please refer to the latest Marine Weather Message (MWWSJU) and
Coastal Waters Forecast (CWFSJU) issued by the National Weather
service WFO San Juan PR.

&&

.PRELIMINARY POINT TEMPS/POPS...
SJU 89 80 89 79 / 20 60 60 40
STT 92 81 91 80 / 40 50 50 70

&&
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Re: Caribbean - Central America Weather

#19583 Postby cycloneye » Thu Sep 13, 2018 5:07 am

Area Forecast Discussion
National Weather Service San Juan PR
443 AM AST Thu Sep 13 2018

.SYNOPSIS...Building high pressure ridge north of the region and Tropical
Storm Isaac will continue to dominate the local synoptic pattern across
the region through Friday as Tropical Storm Isaac passes south of the
forecast area. Small infrequent bands of low clouds and showers generated
from the distant Tropical storm Isaac will make its way across the
local region and bring periods of moderate to heavy rains and gusty
winds across the coastal waters and parts of the islands during the
rest of the morning. A fairly moist and unstable weather pattern is
forecast through most of the week and into early next week with winds
becoming more southeasterly by Friday and into the weekend.

&&

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

Isaac`s forward outer band will continue to stream across the region
through this evening. This will feed squally weather conditions
along with gusty winds across the forecast area. First, streamer-
like scattered to numerous showers will quickly move across the
waters and into coastal areas of northern and eastern Puerto Rico
and the U.S. Virgin Islands during the early morning hours, then
these showers will affect the rest of the forecast area during the
late morning and early afternoon hours as this band progress
westward. The moisture associated to this band in combination with
diurnal and local effects will trigger afternoon convection over
most of Puerto Rico, with the strongest activity focused over the
interior and southwestern portions of the island.

Following the departure of the aforementioned outer rain band,
occasional rain bands will quickly move across the forecast area.
Although a slight break in showers and thunderstorm activity can be
expected, a secondary event of showers and thunderstorms is expected
as Isaac approaches and moves south of the local islands late
tonight into Friday. Showers and thunderstorms will first affect the
U.S. Virgin Islands and the eastern half of Puerto Rico during the
overnight hours. As the storm progress westward, the coverage and
intensity of the activity will increase, affecting most of the local
islands and waters through late Friday night. Based in the current
forecast, total rainfall accumulations are expected to range between
1 and 2 inches with isolated amounts up to 4 inches between today
and Saturday. Thus, urban and small stream flooding, rapid rises
along rivers, and mudslides near steep terrain are highly likely
during this forecast period.

Lingering moisture from Isaac will remain over the forecast area on
Saturday, resulting in a relative seasonal pattern. That is, showers
streaming over the waters into coastal areas of southern and eastern
Puerto Rico during the overnight and early morning hours, followed
by afternoon convection over the interior and western Puerto Rico.
The potential for urban and small stream flooding remains possible
on Saturday.

.LONG TERM...Sunday through Friday...
Following the passage of Isaac south of the region, a moist
southeasterly flow is expected to prevail through most of the
upcoming weekend and into early next week. Recent model guidance
continued to suggest layered precipitable water values in excess
of 2 inches into early next week. The proximity of a retrograding
Tutt low and another tropical wave forecast to move across the region
during the early part of next week will maintain a moist and unstable
environment trough at least Wednesday, with a gradual improvement
during the latter part of the week. The overall pattern should therefore
support periods of moderate to heavy rainfall with showers and isolated
thunderstorm activity each day at least through mid week followed by
lesser potential for shower development and drier conditions expected
thereafter.


&&

.AVIATION...VFR conditions will prevail across area airports for most
of the forecast period. However, there are chances for isolated
passing showers through the mid morning hours along the northern
coasts facing terminals. Model guidance bring a drier airmass across
the area for the first part of the afternoon and therefore, limited
shower activity is anticipated with the exception of the typical
afternoon convection over TJMZ around 21Z to 00Z FRI. Cigs of SCT020-
030 with a second cloud deck of SCT030 to BKN40 are expected across
the area through the forecast period. E to NE winds of 5 to 15 knots
and gusts up to 20 knots are expect for this cycle.

&&

.MARINE...Seas at buoy 41044 have ranged between 8 to 10 feet, while
the northern buoy 41043 was around 7 feet overnight through the early
morning. These wind generated waves and north and east swell action
is expected to spread across the regional waters and passages through
Friday bringing deteriorating and hazardous sea conditions. Winds
and seas are forecast to increase and reach 8 to 10 feet through Friday
with occasional seas up to as much as 12 feet over the offshore Caribbean
waters and the Anegada passage. Occasional gusts and squalls will remain
possible across the local waters in advance of the tropical storm as
it is still forecast to pass south of the region. Small craft advisories
will therefore eventually be required for most of the local waters and
passages beginning today and continuing through Friday. Please refer
to the latest Coastal Waters Forecast and Marine Weather Message issued
by the National Weather Service WFO San Juan PR.

&&

.PRELIMINARY POINT TEMPS/POPS...
SJU 88 80 86 78 / 70 90 90 70
STT 92 80 86 78 / 40 70 80 40
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Re: Caribbean - Central America Weather

#19584 Postby cycloneye » Thu Sep 13, 2018 11:11 am

FLASH FLOOD WATCH...CORRECTED
National Weather Service San Juan PR
1110 AM AST Thu Sep 13 2018

...Periods of heavy rainfall are expected late tonight into Friday
as Isaac moves south of the area...

.There is a high risk of flash flooding across eastern sections of
Puerto Rico as Isaac moves south of the area.

PRZ001>004-006-007-132300-
/O.COR.TJSJ.FF.A.0002.180913T2200Z-180915T0000Z/
/00000.0.ER.000000T0000Z.000000T0000Z.000000T0000Z.OO/
San Juan and Vicinity-Northeast-Southeast-Eastern Interior-
Central Interior-Ponce and Vicinity-
Including the cities of Bayamon, Carolina, Catano, Guaynabo,
San Juan, Toa Alta, Toa Baja, Trujillo Alto, Ceiba, Canovanas,
Fajardo, Humacao, Loiza, Luquillo, Naguabo, Rio Grande, Arroyo,
Guayama, Maunabo, Patillas, Salinas, Yabucoa, Aguas Buenas,
Caguas, Cayey, Cidra, Comerio, Gurabo, Juncos, Las Piedras,
San Lorenzo, Aibonito, Baranquitas, Ciales, Coamo, Corozal,
Jayuya, Morovis, Naranjito, Orocovis, Villalba, Guayanilla,
Juana Diaz, Yauco, Penuelas, Ponce, and Santa Isabel
1110 AM AST Thu Sep 13 2018

...FLASH FLOOD WATCH IN EFFECT FROM 6 PM AST THIS EVENING THROUGH
FRIDAY EVENING...

The National Weather Service in San Juan has issued a

* Flash Flood Watch for a portion of Puerto Rico, including the
following areas, Central Interior, Eastern Interior,
Northeast, Ponce and Vicinity, San Juan and Vicinity, and
Southeast.

* From 6 PM AST this evening through Friday evening

* As the outer bands of Tropical Storm Isaac move closer to the
forecast area, showers and thunderstorms with some gusty winds
will begin to affect the local islands as early as late tonight
into early Friday morning. The shower and thunder activity is
expected to become more frequent by the mid morning hours on
Friday and continue through at least Friday night.

Although fast-moving showers and thunderstorms are anticipated,
the rainfall activity could be enhanced by the local terrain.
Based on the latest forecast and the complexity of the terrain,
rainfall totals will range between 2 to 4 inches with locally
higher amounts possible across the south central, southeast and
east sections of Puerto Rico. As a result, there is a moderate
to high risk of flash flooding across these areas, and a Flash
Flood Watch has been issued.

Possible impacts include, flooding of rivers and small streams
as well as mud slides in areas of steep terrain.

Elsewhere, including Vieques, Culebra, Saint Thomas and
Saint Croix, lower rainfall accumulations are expected. Rainfall
totals will range 1 to 2 inches and therefore the risk for flash
flooding across western Puerto Rico and the outlying islands is
low. However, urban flooding is still possible.

PRECAUTIONARY/PREPAREDNESS ACTIONS...

A Flash Flood Watch means that conditions may develop that lead
to flash flooding. Flash flooding is a very dangerous situation.

You should monitor later forecasts and be prepared to take action
should Flash Flood Warnings be issued.

&&
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Re: Caribbean - Central America Weather

#19585 Postby cycloneye » Fri Sep 14, 2018 5:27 am

Area Forecast Discussion
National Weather Service San Juan PR
511 AM AST Fri Sep 14 2018

.SYNOPSIS...Recently downgraded Tropical Depression Isaac continued
westward across the the eastern Caribbean spreading rainbands with
isolated thunderstorms, heavy showers and squalls with gusty winds
across the forecast area. Isaac will continue to move south of the
region today through Saturday. The strong local winds and gusty conditions
are expected to gradually decrease by Saturday while becoming more southeasterly
over the rest of the weekend. The moist southeasterly flow is expected
to persist into early next week as fair amounts of tropical moisture
will trail Isaac and be lifted across the region. The potential for
periods of locally heavy rains across portions of the islands will
therefore persist at least through Saturday. As a result, there is
high potential for flash flooding as well as urban and small stream
flooding across parts of Puerto Rico and the U.S. Virgin today and
at least until Saturday. An overall wet weather pattern is expected
at least until mid week next week.

&&

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

Downgraded Tropical Depression Isaac, currently south of the U.S. Virgin
Islands continues to move west across the Caribbean. The outer bands
of Isaac will continue to affect the local area through the day, bringing
gusty winds up to around 35 mph and moderate to heavy rain with a few
thunderstorms. The areas with the highest rainfall accumulations are
expected to be across the eastern half of Puerto Rico with particular
emphasis in the southeastern sections, where 2 to 4 inches are possible
with isolated higher amounts. The USVI will experience brief moments
of heavy rain and rainfall totals of 1 to 2 inches are expected. Given
the increase in cloudiness expected today, the max temps are expected
to be in the mid 80s across the lower elevations and in the upper 70s
to low 80s across the higher elevations. A flash flood watch remains
in effect until this evening for the eastern half of PR and the south
central municipalities. However, latest high resolution model guidance
suggests that the moderate to heavy rainfall could persist into the
evening hours for the eastern and northeastern sections of PR. Bottom
line is that even though Isaac is south of the local islands, periods
of moderate to heavy rain with a few thunderstorms and strong gusty
winds are expected today across the local waters, USVI and Puerto
Rico.

On Saturday, moisture will linger across the local area, causing showers
and thunderstorms which will affect the local islands. With the prevailing
southerly wind flow expected, the areas with the highest chance of rain
is expected to be across the south and southeast sections of PR as
well as the northwestern and north central sections and portions of
the USVI. Then on Sunday, some moisture will combine with local effects
to cause afternoon showers and thunderstorms across the northwestern
and north central sections of PR. Friday through Sunday are expected
to be fairly wet.

.LONG TERM...Monday through Friday...
Surface high pressure ridge will extend into the northeast Caribbean
Monday through Tuesday allowing a return of a more easterly wind flow
across the region. Isolated to scattered showers and isolated thunderstorms
will remain possible through Tuesday, mainly over central and western
Puerto Rico during the afternoons. The high is forecast to build north
and east of the region through at least mid week while increasing the
easterly trade winds. Another tropical wave is forecast to approach
and move across the area late Tuesday through Wednesday bringing additional
moisture and instability to the region. This along with the proximity
of a Tutt low will make conditions favorable for enhanced afternoon
convection at least Wednesday through Thursday. Drier conditions and
decreasing precipitable water and moisture content across the region
is forecast for Friday. By then the Tutt is to shift north and west
of the region supporting stable conditions aloft with lesser daytime
convection expected.

&&

.AVIATION...Gusty winds and showery conditions with Vrb cigs going
back and forth between VFR and MVFR expected for most of the day.
Gusts up to 35 knots are expect with lines of showers associated
with rain bands from Isaac. Also, as these showers move across
area terminals, expect visibilities to drop 3SM-4SM and even less
depending on the intensity of the passing showers. Northeasterly
winds will remain through early this afternoon and then shift to
the southeast as Isaac continues to move westward.

&&

.MARINE UPDATE...Marine conditions continued to deteriorate
overnight across the local waters especially over the Caribbean
waters and the Anegada passage, as Tropical Depression Isaac
continued to cross the Eastern Caribbean and move south of the
local islands. Recent observations and surrounding buoys suggested
sustained winds between 15-20 kts with occasional gusts between
30 to 35 kts across the regional waters. Seas were ranging between
8-12 feet occasionally higher across the local waters and
passages and are expected to continue today. Isolated
thunderstorms with heavy showers accompanying rainbands and
occasional squalls are expected to continue over the local waters
creating hazardous marine conditions during the rest of today
through at least Saturday. Small craft advisories continue for
most of the local waters.

&&

.PRELIMINARY POINT TEMPS/POPS...
SJU 87 77 88 78 / 90 70 40 40
STT 89 79 86 79 / 90 60 40 40

&&

.SJU WATCHES/WARNINGS/ADVISORIES...
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Re: Caribbean - Central America Weather

#19586 Postby cycloneye » Sat Sep 15, 2018 5:24 am

Area Forecast Discussion
National Weather Service San Juan PR
510 AM AST Sat Sep 15 2018

.SYNOPSIS...High pressure ridge aloft shifting west of the region and
a Tutt low lifting northeast of the region will maintain weak diffluence
and instability aloft through Sunday. Deep tropical moisture from the
remnants of Isaac in the prevailing south southeast wind flow
will also maintain a moist and unstable environment through the
weekend. A gradual improvement is expected early next week as the
Tutt lifts farther north of the region. Another tropical wave is
forecast to arrive and move across the region Wednesday through
Thursday.

&&

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

The remnants of Isaac, continue to move away from the local islands
and it is currently south of Hispaniola as it continues to move west.
However, deep moisture will linger across the local islands through
Sunday, with less but still good moisture lingering into Monday as
well. A mesoscale convective system has persisted south of the local
waters through most of the night and it is bringing lines of showers
with isolated thunderstorms into our local waters, but these have
been generally short lived and small in coverage. These lines of
showers and isolated thunderstorms are expected across the Caribbean
waters through the morning today.

There has been a great deal of discrepancy between the model guidance,
making the forecast for today very difficult. Deep moisture will linger
today and there is some divergence in the upper levels, but there is
a lot of cloudiness which should limit convection in the afternoon.
However, the northern portions of Puerto Rico may have a break in
the clouds, which will combine with the diurnal heating to cause showers
and thunderstorms, while eastern and southern PR and the USVI could
still observe showers and thunderstorms as the SSE wind flow brings
showers to the local area. Maximum daytime temps today are expected
to be in the mid to upper 80s across the lower elevations and in
the lower 80s across the higher elevations.

Sunday looks somewhat similar to what we expect today with the exception
of the advective rain. For Sunday, the afternoon showers and thunderstorms
across the north and northwest sections of PR will likely be due to
a combination of the deep moisture and diurnal local effects. Even
though there is plenty of moisture, the USVI is expected to observe
mainly isolated showers on Sunday. Then on Monday, moisture decreases
but there is still enough to combine with the local effects of Puerto
Rico to cause showers and thunderstorms across the northwestern quadrant,
while the rest of PR and the USVI is expected to observe isolated to
briefly scattered showers.

.LONG TERM... Tuesday through Saturday...
Surface high pressure ridge will extend into the northeast Caribbean
through Tuesday allowing a return of a more easterly wind flow across
the region. Isolated to scattered showers and thunderstorms will remain
possible through Tuesday, mainly over central and western Puerto Rico
during the afternoons. The high is forecast to build north and east
of the region through Wednesday while strengthening the easterly trade
winds. Another tropical wave is forecast to approach and move across
the area Wednesday through Thursday bringing additional moisture and
instability to the region. This along with the proximity of a Tutt
low will make conditions favorable for enhanced afternoon convection
at least through Thursday. Drier and more stable conditions with decreasing
layered precipitable water and moisture transport is forecast across
the area Friday through Saturday. By then, the Tutt is to shift north
and west of the region supporting stable conditions aloft with lesser
daytime convection expected. However, occasional patches of trade
wind moisture may continue to bring periods of passing early morning
showers along portions of the north and east coastal sections of the
islands.

&&

.AVIATION...Mainly VFR conds expected today through 15/16Z across the
local terminals with VCSH through the day. Afternoon convection may
cause VCTS at TJBQ and TJSJ after 15/16Z. Dense cloud layer will
cause ceilings through the local terminals between FL040-080 through
the period. Winds will be with a strong southerly component except
for TJBQ and TJSJ. Wx improving tonight with only ISOLD/SCT SHRA
after 16/00Z.

&&

.MARINE...Moderate to fresh east to southeast winds will prevail over
the regional waters today. A gradually subsiding easterly swell will
continue across the local waters and passages today resulting in hazardous
seas. Occasional lines of showers and thunderstorms with brief wind
gusts will remain possible mainly over the Caribbean waters and the
Mona passage during the rest of the morning hours.

&&

.PRELIMINARY POINT TEMPS/POPS...
SJU 88 77 89 77 / 60 50 40 40
STT 88 77 88 79 / 60 40 40 40
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Re: Caribbean - Central America Weather

#19587 Postby cycloneye » Sun Sep 16, 2018 6:01 am

Area Forecast Discussion
National Weather Service San Juan PR
520 AM AST Sun Sep 16 2018

.SYNOPSIS...Deep layered moist southeasterly flow will continue
across the region today. Tutt low and associated trough will
continue to lift northwards across the region to maintain and
enhance instability across the region through at least Monday. The
next tropical wave is forecast to approach and move across the
region Wednesday through Thursday of the upcoming week.

&&

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

There is above normal moisture that will linger across the area
through Monday, with slightly less moisture expected on Tuesday.
This moisture will combine with an upper trough lifting to the
north northeast of the local islands. This combination will give
us showers and isolated thunderstorms across the general area, but
more persistent showers and thunderstorms in areas of sea breeze
convergence such as the north and northwestern sections of Puerto
Rico in the afternoon hours. The latest guidance indicates that in
the morning and nighttime hours, the shower activity should be
isolated to perhaps scattered across some areas. However, the
diurnal heating will combine with the moisture and upper level
instability for these showers and thunderstorms to develop.

The southeasterly wind flow may cause slightly hotter than normal
temperatures across northern Puerto Rico today, especially if the
afternoon showers were to develop a bit later than expected. The
local winds are expected to remain somewhat light, but having a more
easterly component on Monday and Tuesday, so the sea breeze
development should keep the daytime max temps across northern PR
near normal with high in the upper 80s and close to 90 degrees in
some areas.

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

Tropical wave moving across the region Wednesday through Thursday
is forecast to bring additional moisture and instability to the
region,therefore increasing the potential for periods of enhanced
showers and thunderstorms across the coastal waters and local
islands. Thereafter, the surface high across the northeast
Atlantic is to build and spread north of the region while
strengthening the easterly trade winds. The aforementioned tutt
low is to lift north and west of the region by the latter part of
the work week, as high pressure ridge will build aloft. This in
turn will increase stability aloft and help to erode low level
moisture transport, with a somewhat drier airmass to prevail
across the region during the rest of the week and into the
weekend. However, passing trade wind showers during the early morning
hours, followed by periods of locally and diurnally induced afternoon
convection cannot be ruled out each day. The afternoon convection
should be focused mainly over parts of the windward sections during
the morning hours and over portions of central and west Puerto Rico
during the afternoon hours. Drier and more stable conditions with
decreasing layered precipitable water content and moisture transport
is forecast across the area Friday through Sunday. By then, the
Tutt is to shift northwest of the region supporting stable conditions
aloft with lesser daytime convection. Occasional patches of trade
wind moisture may however continue to bring periods of passing early
morning showers along portions of the north and east coastal sections
of the islands.

&&

.AVIATION....Even though SHRA/TSRA activity is expected today, mainly
VFR conds are expected at the actual terminals. VCSH/VCTS is expected
across TJSJ and TJPS through 16/12Z. Then the afternoon convection
should cause VCTS at TJBQ and TJMZ, with also possibly TJSJ after
16/17Z. Winds will be mainly from the SE with sea breeze variations
at around 10KT.

&&

.MARINE...Winds and seas will continue to gradually diminish and
subside across most of the regional waters today. However, a
northeasterly swell will continue to affect the local waters and
passages. Small craft operators should therefore continue to
exercise caution.

&&

.PRELIMINARY POINT TEMPS/POPS...
SJU 89 79 89 80 / 50 20 50 40
STT 88 79 88 81 / 50 20 20 20
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Re: Caribbean - Central America Weather

#19588 Postby cycloneye » Tue Sep 18, 2018 5:29 am

Area Forecast Discussion
National Weather Service San Juan PR
415 AM AST Tue Sep 18 2018

.SYNOPSIS...Surface high pressure will build over the north
central Atlantic through midweek. This will maintain a moderate
to locally fresh east to southeast wind flow across the region. A
tropical wave is forecast to move across the Eastern Caribbean
between Wednesday and Thursday, increasing shower and thunderstorm
activity across the local forecast area.


&&

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

There is above normal moisture that will linger across the area
through the day today, a slot of dry air is expected overnight
tonight before a tropical wave moves in on Wednesday. This available
moisture will combine with an upper trough to the northwest of the
local islands that is still lingering and will continue through
Wednesday. This combination will once again today and Wednesday give
us showers and isolated thunderstorms, particularly across areas of
sea breeze convergence such as the north and northwestern quadrant
of Puerto Rico in the afternoon hours. The latest guidance still
indicates that in the morning and nighttime hours, the shower
activity should be isolated across the eastern sections of PR, USVI
and the local waters. A pulse of Saharan dust is expected to make a
return on Thursday, bringing much drier air to the local area right
after the tropical wave passes.

Easterly winds are expected to return. Near normal temperatures
across northern Puerto Rico are expected today. The local winds are
expected to be at 5 to 10 mph over land areas, but up to 15 mph or
so over the coastal areas. A increase on moisture is forecast
from Friday night through at least Tuesday, increasing the chances
of afternoon convection along the Cordillera Central and western
portions of Puerto Rico.

.LONG TERM...Friday through Tuesday

A tropical wave and a slight increase in tropical moisture along
with a wind surge across the region Wednesday through Thursday
followed by a rapid drying trend thereafter, due to the arrival of
moderate to possible high concetrations of suspended dust
particulates in an extensive Saharan air layer.

&&

.AVIATION...VFR conds expected across the local terminals through
18/17Z. Winds will be mainly from the east at around 10KT after
18/14Z with sea breeze variations developing, becoming light and
variable after 18/23Z. VCSH/VCTS expected at TJBQ and TJMZ after
18/17Z as SHRA/TSRA develops over W-NW PR in the afternoon, possibly
at TJSJ as well. ISOLD SHRA expected elsewhere in PR and USVI
through the forecast period.


&&

.MARINE...Sea will continue 5 feet or less and winds 10 to 15 kts
through at least Wednesday. A slight increse on winds and seas is
forecast to ocurr across the local waters late tuesday as a weak
tropical is expected to move across the local waters.


&&

.PRELIMINARY POINT TEMPS/POPS...
SJU 89 80 90 80 / 20 20 20 20
STT 90 80 89 82 / 40 10 20 20
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Re: Caribbean - Central America Weather

#19589 Postby cycloneye » Wed Sep 19, 2018 7:04 am

Area Forecast Discussion...CORRECTED
National Weather Service San Juan PR
425 AM AST Wed Sep 19 2018

.SYNOPSIS...Drier and relatively stable air mass with Saharan
Dust will reach the local on Wednesday. A tropical wave east of
the Lesser Antilles will pass mainly south of the local area late
tonight into Thursday morning, with some enhancement in the
shower activity over the Caribbean waters. Generally stable
conditions will prevail the rest of the week as mid-level ridge
dominates the northeast Caribbean region.


&&

.SHORT TERM...Today through Friday...
Tranquil weather is expected to prevail across the region over the
next several days, with temperatures in the upper 80s to lower 90s.
The TUTT low to the north of Puerto Rico will continue to move away
from the area, thus decreasing instability needed for shower and
thunderstorm development. Although instability will decrease showers
and isolated thunderstorms are still possible as a result of, local
and diurnal effects.

The low to mid level ridge to the east of the region will build
across Puerto Rico and the U.S. Virgin Islands today and maintain
their hold through the end of the week. A strong trade wind cap or
inversion will develop as a result of, the low and mid level
ridge. The inversions created by the ridges will remain through
Friday, thus convection will be limited except over the western
and interior areas of Puerto Rico during the afternoon. These
ridges will also bring dry Saharan air as well as a plume of dust
with them. The Saharan dust is forecast to peak on Thursday, but
hazy skies will remain through the weekend.

A weak tropical wave moved into the southern Caribbean waters this
morning and is expected to remain well south of the local Islands
chains, but the moisture could cause showers over the U.S Virgin
Islands and easter areas of Puerto Rico during this morning.

.LONG TERM...Saturday through Thursday

A mid-level ridge will extend southward into the northeast
Caribbean, limiting thunderstorms development across the local
forecast area from Saturday through at least Tuesday. Available
moisture will be enough for afternoon showers to develop over the
interior and western portions of Puerto Rico throughout this
from Saturday through Monday.

A tropical wave will move across the local Caribbean waters
between Tuesday night and Wednesday night increasing the shower
and thunderstorms coverage across the local forecast area,


&&

.AVIATION...VFR conds will prevail across all terminal sites through
19/15Z, then SHRA/VCTS are forecast to develop across the western
terminal sites. SFC winds will be out of the east at 15 to 20 kts
with higher gust possible.


&&

.MARINE...A tropical wave will continue to move across the local
waters today slightly increasing the winds and seas across mainly
the Caribbean waters. Expect seas up to 5 feet and winds up to 20
knots. Small craft operators should exercise caution across the
Caribbean waters.

A series of low pressures will develop across the Atlantic waters generateing
different pulses of northerly swells over our local waters. The first
pulse of the long period northerly swell is forecast to reach our local
Atlantic waters between late Saturday and early Sunday morning. The
second pulse will have a more NE component and will be reaching
our local Atlantic waters on Tuesday morning.

&&

.PRELIMINARY POINT TEMPS/POPS...
SJU 90 80 90 79 / 40 40 40 40
STT 90 81 89 81 / 20 40 40 40
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Re: Caribbean - Central America Weather

#19590 Postby cycloneye » Thu Sep 20, 2018 5:26 am

Area Forecast Discussion
National Weather Service San Juan PR
433 AM AST Thu Sep 20 2018

.SYNOPSIS...
Hazy conditions are expected to continue over the next several
days due to Saharan dust. The dust is forecast to peak on Friday
with improving conditions during the weekend. Strong tradewinds
and a dry Saharan airmass will limit shower activity to the
western and interior areas of Puerto Rico over the next several
days. Although, convection will be limited isolated showers are
possible for the eastern areas of Puerto Rico and the U.S. Virgin
Islands during the afternoon. As the trade winds relax during the
weekend moisture will increase, but skew-T analysis shows a
rather strong dry layer extending from 700 to 500 mb through early
Tuesday. Tuesday moisture will increase ahead of an approaching
tropical wave from the east. This wave is forecast to remain south
of Puerto Rico on Wednesday, but will help aid in the development
of showers and thunderstorms across most of the area.

&&

.SHORT TERM...Today through Saturday

Variably cloudy skies prevailed overnight and early this morning
across the local islands with scattered to numerous showers and
isolated thunderstorms noted across the US Virgin Islands as well as
south and eastern Puerto Rico. Rainfall accumulations associated
with these showers and thunderstorms were between 1 and 2 inches,
particularly across the eastern coastal areas of Puerto Rico.
Coastal temperatures were in the upper 70s under east southeast
winds at 10 mph or less.

As the tropical wave continues to move away, a drier and dusty air
mass is expected to move in from the east. This drier and dusty air
mass combined with a mid to upper level ridge will result in fair
weather conditions later today through at least Friday. The ridge
aloft is then expected to weaken the upcoming weekend as an upper
level trough develops across the tropical Atlantic into the eastern
Caribbean. Trofiness aloft will then allow moisture transport early
in the weekend. At lower levels, east southeast will continue
throughout the day becoming east northeast by Saturday as a surface
high north of the area shifts northeast.

Therefore, still expect a few passing showers early this morning
with the chance for shower and thunderstorm activity quickly
decreasing later today. However, lingering moisture will result in
locally induced showers and a few thunderstorms over NW PR this
afternoon. A dry and stable weather pattern is expected on Friday
with rain-free conditions across most of the forecast area. A
seasonal weather pattern is expected to return on Saturday with
passing showers across windward areas and showers and thunderstorms
developing across the interior and west Puerto Rico in the afternoon.

.LONG TERM...Sunday through Saturday...
The long term period will be defined by upper
level troughs and weak tropical waves. Model guidance has a weak
trough developing to the northeast of the Leeward Islands on
Sunday with moisture filtering into area on the backside of the
trough. This trough is forecast to remain over the area through
most of the long term Period. Tuesday moisture will increase
ahead of a tropical wave that is forecast to move into the
Caribbean waters on Wednesday. Therfore a increase in showers and
thunderstorms are expected Tuesday through Wednesday as a result
of the increasing moisture. A moist airmass is expected to remain
over the region through the end of the workweek.

&&

AVIATION...VFR conds are expected to prevail through the forecast
cycle with an isolated SHRA possible in and around JSJ in the
morning. Aft 20/16z, brief periods of MVFR conds are possible in and
around JBQ in SHRA/TSRA through about 20/22z. ESE winds 10 to 15
knots to continue with some sea breeze variations.

&&

.MARINE...
Seas will range from 4 to 5 feet with an occasional seas up to 6
feet across all the local and outer waters except for the waters
of northwestern Puerto Rico. Winds will range from 10 to 15 kts
with higher gusts possible today. A moderate risk of rip currents
for the northern, southern and portions of the eastern beaches of
Puerto Rico today.

&&

.PRELIMINARY POINT TEMPS/POPS...
SJU 86 80 85 80 / 30 10 60 60
STT 83 82 82 81 / 40 30 30 30
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Re: Caribbean - Central America Weather

#19591 Postby cycloneye » Sat Sep 22, 2018 6:55 am

Area Forecast Discussion...CORRECTED
National Weather Service San Juan PR
517 AM AST Sat Sep 22 2018

.SYNOPSIS...

Saharan dust will continue to diminish today, but
hazy skies are possible due to lingering dust. Scattered showers
were observed during the overnight hours, due to an increase in
moisture which moved in on the back side of the TUTT low that is
currently positioned to the northeast of the Leeward Islands. The
TUTT will erode the mid to upper level high pressure systems, and
weaken the trade wind cap that has limited showers and
thunderstorms over Puerto Rico, and the U.S. Virgin Islands over
the past several days. TD-11 that formed late last night is
forecast to dissipate before reaching the Lesser Antilles early
next week. The moisture from the dissipated depression is forecast
to move into the local area on Tuesday and remain through
Wednesday. Therefore, an increase in showers and thunderstorms are
expected across the U.S. Virgin Islands and eastern Puerto Rico
early Tuesday, then the interior and western Puerto Rico during
the afternoon. Thursday the bulk of the moisture moves out of the
area, but patches of moisture, as well as dry air, will move in
periodically late next week.

&&

Short Term...Today through Monday...

Saharan air layer has moved away from the region, but some dust
could still be present through the morning hours, creating some
hazy skies briefly today. An upper level low northeast of the
region will continue to approach the forecast area during the
short term period. Surface high pressure just north of the region
will continue to provide an east to northeast wind flow today.
Moisture and trade wind showers induced by the upper level low
will continue to stream across the forecast area through the
weekend. This will aid in the development of afternoon convection
over southwestern PR today and across western PR on Sun-Mon as
winds turn more easterly. Forecast soundings are indicating good
lifted index (-7) and somewhat cold temps at 500 MB during the
next couple of days. Therefore, isolated thunderstorms are
expected each afternoon over western PR. Shower and thunderstorm
activity is forecast to increase late on Monday into Tuesday in
association with Tropical Depression Eleven, which is forecast to
pass over the local area as an open trough.

&&

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

A TUTT low will extend westward across most of the local area
through the long-term period. This TUTT low combined with a weak
surface trough will weaken the trade wind cap or inversion over
the region. The weakening of the inversion at 700 to 500 mb will
allow tropical moisture to return from the east, this is depicted
by the SJU skew-T. For Tuesday moisture will increase as a result
of newly formed TD-11, at this time TD-11 is forecast to be an
open wave due to drier air and shear across the Caribbean. Showers
and Thunderstorms will increase on Tuesday and continue through
Wednesday as a result of the increasing moisture and instability
provided by the open wave. Localized urban and small stream
flooding is possible as a result of showers and thunderstorms that
could produced heavy rainfall.

Thursday moisture is forecast to decrease, but patches of
moisture embedded in the trades, as well as drier air will
continue to move periodically over the area. Therefore, showers
are expected across the U.S. Virgin Islands and Puerto Rico during
the morning hours, then showers and isolated thunderstorms will
develop over the interior and western areas of Puerto Rico during
the afternoon.

&&

AVIATION...

Mainly VFR conditions are expected to prevail across all
terminals during the next 24 hours. However, SHRA/TSRA is expected
to develop over the southwestern interior sections of PR btw 16z-
22z. This can result in tempo MVFR conds at TJMZ and VCTS briefly at
TJPS. Surface winds will continue from the east to northeast between
10-15 kt with higher gusts and sea breeze variations after 14z.

&&

.MARINE...

Seas will be below 5 feet across all the local and outer waterways
with east to northeast winds ranging from 10 to 15 kts with higher
gusts. A northerly swell is forecast to increase seas between 4
and 6 feet across the Atlantic Waters and Caribbean Passages on
Sunday, followed by a northeast swell around Tuesday.

&&

.PRELIMINARY POINT TEMPS/POPS...
SJU 89 78 89 78 / 20 20 40 40
STT 90 80 89 80 / 40 30 50 50
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Re: Caribbean - Central America Weather

#19592 Postby cycloneye » Sun Sep 23, 2018 7:42 am

Area Forecast Discussion
National Weather Service San Juan PR
432 AM AST Sun Sep 23 2018

.SYNOPSIS...
A TUTT low/trough as well as low level moisture will increase
showers and thunderstorms over Puerto Rico, and the U.S. Virgin
Islands though the end of next week. Moisture is forecast to move
from the Caribbean across the U.S. Virgin Islands and Puerto Rico
on Tuesday and remain through late Wednesday. Friday another
surge of moisture is forecast to move into the local area and
remain through the weekend. Showers and thunderstorms that
develop each day could cause urban and small stream flooding over
portions of Puerto Rico.


&&

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

For today, diurnally induced afternoon showers and thunderstorms
are expected to develop over the interior and west/northwest
sections of Puerto Rico. Urban and small stream flooding is
possible with this activity. Also, the streamer from el Yunque
could develop and affect San Juan and vicinity during the early
afternoon hours. Across the USVI, showers are expected to develop
around noon, downwind from the islands and move mainly across the
western sections and surrounding waters. Upper level low over the
Leeward Islands will continue to approach the region and induce
passing showers across the regional waters. These showers will
move at times across the USVI and the eastern coastal areas of
Puerto Rico. Shower and thunderstorm activity is forecast to
advect from the east on Monday night into Tuesday, in association
with Tropical Depression Eleven, which is forecast to dissipate
today east of the Windward Islands and move over the local area as
an open trough. The upper level low is forecast to move over and
just west of the area on Tuesday, providing good divergence aloft
while interacting with the remnants of TD#11.

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

An unsettled pattern will persist most of the long-term period as
a result of TUTTS, and upper level troughs that are forecast to
remain over or near the area. Moisture from TD#11 which is
forecast to dissipate east of the area will bring a surge of
moisture over the region on Tuesday. The bulk of the moisture
will arrive on Wednesday, this moisture combined with the TUTT
low will increase instability over the entire area. Therefore, an
increase in showers and thunderstorms is forecast each day, with
the possibility of urban and small stream flooding. A pocket of
drier air is forecast to move in behind the moisture on Friday,
but early Saturday another round of moisture is forecast to lift
out of the Caribbean waters and move across the region, therefore
another round of showers and thunderstorms will develop over
Puerto Rico, and the U.S. Virgin Islands. Model guidance shows
moisture remaining across most of the Caribbean and local waters
through early next week.

&&

.AVIATION...Mainly VFR conditions are expected to prevail across all
terminals during the next 24 hours. However, SHRA/TSRA is expected
to develop over west/northwest PR btw 16z-22z. This can result in
tempo MVFR conds at TJMZ/TJBQ. VCTS/SHRA possible at TJSJ btw 16z-
20z. Also, trade wind showers will continue across the regional
waters, moving briefly across some of the terminals. Low level
winds E-ESE at 10-15 kt with higher gusts and sea breeze variations
after 14z.


&&

.MARINE...Seas will range from 3 to 6 feet with seas occasionally
reaching 8 feet across the local and outer waters. East winds
will prevail between 10 to 15 knots. A northerly swell is forecast
to increase the North Atlantic and Caribbean waters on Tuesday. A
high risk of rip currents exist for the northern beaches of
Puerto Rico today.

&&

.PRELIMINARY POINT TEMPS/POPS...
SJU 90 80 89 80 / 20 40 40 50
STT 89 82 90 82 / 40 40 50 50
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Re: Caribbean - Central America Weather

#19593 Postby cycloneye » Mon Sep 24, 2018 5:08 am

Area Forecast Discussion
National Weather Service San Juan PR
435 AM AST Mon Sep 24 2018

.SYNOPSIS...Trough pattern aloft will support thunderstorm
development each day. The remnants of TD#11 are expected to move
across the area on Tuesday and Wednesday. Another surge in low
level moisture is expected late in the week in association with TC
Kirk. A large long period northerly swell is forecast to affect
the regional waters during the weekend.


&&

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

Mostly clear skies prevailed earlier this morning with winds of 5
to 10 kts. Doppler radar shows a few passing showers mostly over
the local waters. A TUTT low currently east of Culebra will
continue to meander westward through Wednesday. A weak surface
trough is forecast to develop near hispaniola and remain through
the middle of the week. Diurnally induced afternoon showers and
thunderstorms are forecast to develop today across the interior
and western areas of Puerto Rico. Tuesday through Wednesday
showers and thunderstorms are forecast to develop area-wide. These
showers and thunderstorms will be helped by the increasing
instability at the low, mid and upper levels of the atmosphere.
The SJU-GFS shows decreasing 500 mb temperatures and 200 mb
heights. The low level instability will be generated by the
surface trough and the increasing low level moisture provided by
the now dissipated TD#11. Moisture is forecast to increase each
day with the bulk of the moisture arriving late Tuesday or early
Wednesday. Therefore, urban and small stream flooding is likely
each day this week, as a result of favorable environmental
conditions for continued thunderstorm development. This is also
confirmed by the Galvez- Davidson Index (GDI) which measures
stability. The GDI shows values of 25 to 35, and increasing to 35
to 45 on Tuesday and Wednesday. The 35 to 45 values means that
showers and thunderstorms are capable of producing heavy rainfall
that could cause urban and small stream flooding, and ponding of
water on roadways.

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

Trough pattern aloft across the northeastern Caribbean and in the
central Atlantic will support shower and thunderstorm development
through the long term period. Mainly across the interior and
western sections of Puerto Rico. A patch of drier air from an
upper level ridge over the southwestern Atlantic should move from
the north briefly between Thursday and Friday. However, a surge in
low level moisture is expected to return quickly on Friday and
during the weekend in association with the weak Tropical Storm
Kirk. Based on the latest forecast, Kirk is expected to have
fluctuations on intensity and there is still high uncertainty on
the local impacts that it could have once it enters the eastern
Caribbean by the end of the week.


&&

.AVIATION...VFR conds will continue through the reminder of the
prd. SHRA/VCTS are possible due to afternoon convection, which
could cause brief MVRF conds across terminal sites TJBQ, TJMZ and
the western areas of Puerto Rico. Elsewhere, showers are possible
across the eastern areas of Puerto Rico during the afternoon. Sfc
winds out of the east ranging from 10 to 15 kts with higher gusts.


&&

.MARINE...A northerly swell will continue to affect the Atlantic
waters and passages through Wednesday. This will cause seas to
range between 4-6 feet and occasionally up to 8 feet. A moderate
to high risk of rip currents will prevail across the north facing
beaches of the islands for much of the work week. A larger
northerly long period swell is forecast to affect the regional
waters during the weekend. Winds will continue from the east at
10-15 knots. Shower and thunderstorm activity is expected to
increase between Tuesday and Wednesday across the forecast area.


&&

.PRELIMINARY POINT TEMPS/POPS...
SJU 90 78 87 78 / 40 60 70 50
STT 89 79 89 78 / 40 70 70 60
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Re: Caribbean - Central America Weather

#19594 Postby cycloneye » Tue Sep 25, 2018 5:07 am

Area Forecast Discussion
National Weather Service San Juan PR
515 AM AST Tue Sep 25 2018

.SYNOPSIS...Upper level low over the forecast area will linger
over and to the west of the region through Wednesday. The remnants
of Tropical Depression 11 will interact with the upper low and
result in scattered to numerous showers and thunderstorms today.
Trough pattern aloft persists through the weekend and moisture
associated to the remnants of Tropical Storm Kirk increases
between Friday and Saturday.

&&

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

Variably to mostly cloudy skies expected throughout the period. As
the remnants of Tropical Depression (TD) 11 continues to move across
the forecast area and an upper level trough meanders westward over
the northeastern Caribbean Sea, the risk for deep convection remains
high until Wednesday due to high moisture content and favorable
upper level conditions across the region. Streamer-like showers and
thunderstorms will move across the local waters into portions of
eastern Puerto Rico and the U.S. Virgin Islands each night. Then,
local effects and diurnal heating will enhance afternoon convection
over the entire forecast area, particularly over portions of the
interior and western Puerto Rico. Although the bulk of the moisture
associated to TD 11 is expected to depart late Wednesday night,
lingering moisture and favorable upper level conditions will create
a similar weather pattern on Thursday. Given that this activity is
expected to result in total rainfall accumulations between 1 and 2
inches with isolated higher amounts, the threat of urban and small
stream flooding, mudslides near steep terrain and rapid rises along
river and its tributaries will continue at least until Thursday.

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

An upper level trough pattern will persist over and north of the
region through the long term period. This will enhance the
potential for shower and thunderstorm development each afternoon,
mainly over the interior and western sections of PR as well across
the San Juan metro area. Shower and thunderstorm activity as well
as breezy conditions are expected between Friday and Saturday in
association to what was Tropical Storm Kirk. A tropical wave is
forecast to move across the eastern Caribbean by midweek,
increasing shower and thunderstorm activity once again over the
forecast area.

&&

.AVIATION...As the remnants of TD eleven continues to approach the
forecast area from the east, VCTS/VCSH possible with brief MVFR
conditions until early morning at most terminals, except
TJPS/TJMZ/TJBQ. Then, VCTS/VCSH expected across all terminals during
the day, with MVFR conditions possible during the afternoon at
TJSJ/TJMZ/TJBQ. Surface winds from the east between 10-15 knots with
higher gusts. MVFR conditions posible over the coastal waters and en
route between the islands.

&&

.MARINE...Showers and thunderstorms across the regional waters
will create locally higher seas and gusty winds through the day.
Northerly swell will cause a high risk of rip currents along the
north facing beAches of the islands. Seas will range between 4-6
feet across the regional waters, except in the offshore Atlantic
where seas up to 7 feet are expected today and a small craft
advisory is in effect. A larger long period northerly swell is
forecast to move across the regional waters during the weekend.


&&

.PRELIMINARY POINT TEMPS/POPS...
SJU 87 78 87 78 / 60 50 40 40
STT 88 78 90 79 / 70 70 40 40
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Re: Caribbean - Central America Weather

#19595 Postby cycloneye » Wed Sep 26, 2018 5:05 am

Area Forecast Discussion
National Weather Service San Juan PR
532 AM AST Wed Sep 26 2018

.SYNOPSIS...A meandering TUTT low and induced surface trough will
combined with lingering moisture from a departing tropical wave
will result in enhanced shower and thunderstorms activity across
the forecast area today. Tropical Storm Kirk will move into the
eastern Caribbean and south of the forecast area late Friday night
through the weekend, bringing shower and thunderstorm activity as
well as breezy conditions. Although conditions will somewhat
improve by early next week, the next tropical wave will approach
the eastern Caribbean by midweek, increasing shower and
thunderstorm activity across the forecast area.


&&

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

A meandering TUTT low is inducing a surface trough which combined
with the available moisture and the northeast wind flow will
continue to bring passing showers across the north and east sections
of Puerto Rico and the U.S. Virgin Islands today. The south and west
sections of Puerto Rico can expect a mixture of sunshine and clouds
through at least mid-morning. However, favorable upper level
dynamics, local effects and diurnal heating will enhance afternoon
convection over most of the islands, especially over portions of the
interior and southwest Puerto Rico. Any persistent moderate to heavy
rainfall event could result in urban and small stream flooding,
mudslides along steep terrains and rapid river rises.

The upper level trough pattern will result in unsettled weather
conditions through much of the short term period. For that reason,
the potential for night time and early morning passing showers
across the U.S. Virgin Islands and the windward sections of Puerto
Rico will remain high. Followed by the development of afternoon
showers and thunderstorms across the interior and western sections
of PR.

On the latest forecast track from the National Hurricane Center, the
center of Kirk is expected to move well south of the islands as a
Tropical Depression. However, model guidance are suggesting the
proximity of enough tropical moisture which combined with the upper
level trough and local effect could trigger enhance deep convection
by Friday afternoon.


.LONG TERM...Saturday through Thursday...

Based on the latest advisory from the National Hurricane Center, a
mid level ridge will continue to steer Tropical Storm Kirk across
the eastern Caribbean late Friday night into early Saturday
morning. Specifics on the impacts this system could bring to the
local area are uncertain at this time. This lack of certainty is
due to (1) variations in the time of arrival, (2) whether it
remains as a tropical cyclone or not, and (3) the organization of
the system as it moves south of the forecast area. Nevertheless,
shower and thunderstorm activity, as well as breezy conditions are
expected across the local area through the weekend.

From late Sunday night through Wednesday afternoon, moisture
content and favorable upper level conditions are expected to
decrease. However, there will be enough moisture content that
combined with local effects and diurnal heating will result in
afternoon convection across portions of the interior and western
Puerto Rico, as well as downwind from El Yunque and the local
islands during this period. Overnight and early morning streamer-
like showers are also possible. The next tropical wave is
forecast to move across the eastern Caribbean late Wednesday into
Thursday, increasing shower and thunderstorm activity once again
over the forecast area.


&&

.AVIATION...VCSH expected across TJSJ/TJBQ/TIST/TISX through the
morning hours. SHRA/TSRA are forecast across the eastern sections,
and could impact TJSJ/TIST. Then this activity will spread across
the interior and western sections to affect TJMZ/TJPS and possibly
TJSJ/TIST. Winds will continue from the NE at 5 to 10 knots
increasing at 10 to 20 knots after 26/13z.


&&

.MARINE...Small craft advisories continue in effect for the
Atlantic waters and the local passages until at least 6 PM AST
this afternoon for seas up to 7 feet. These advisories will
continue for the offshore and nearshore Atlantic waters tonight
and Thursday. Elsewhere, seas will be mainly up to 5 or 6 feet,
therefore small craft operators are urged to exercise caution
across areas where seas up to 6 feet are expected. Shower and
thunderstorm activity will continue as favorable upper level
conditions and lingering moisture remains across the local area.


&&

.PRELIMINARY POINT TEMPS/POPS...
SJU 88 78 89 79 / 60 60 30 30
STT 91 80 91 80 / 50 60 30 50
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Re: Caribbean - Central America Weather

#19596 Postby cycloneye » Thu Sep 27, 2018 5:10 am

Hazardous Weather Outlook
National Weather Service San Juan PR
554 AM AST Thu Sep 27 2018

AMZ710>745-PRZ001>013-281000-
San Juan and Vicinity-Northeast-Southeast-Eastern Interior-
North Central-Central Interior-Ponce and Vicinity-Nortwest-
Western Interior-Mayaguez and Vicinity-Southwest-Culebra-Vieques-
The nearshore and off shore Atlantic and Caribbean Coastal Waters-
554 AM AST Thu Sep 27 2018

This Hazardous Weather Outlook is for Puerto Rico and the adjacent
Atlantic Coastal Waters.

.Day One...Today and Tonight

.Thunderstorms...There is a chance of thunderstorms with heavy rainfall
and brief gusty winds across most of the island, especially across
the interior and west to southwest sections during the afternoon
hours.

.Flooding...Heavy rains will lead to urban and small stream flooding,
as well as ponding of water on roadways and in poor drainage
areas. Mudslides will remain possible in areas of steep terrain.

.Wind...Sustained winds in excess of 20 mph (17 kts) expected
across the surrounding waters of Puerto Rico.

.Waves...Choppy/Rough seas up to 7 feet expected across the Atlantic
waters and Caribbean Passages.

.Rip Currents...There is a high risk of rip currents for beaches
along the northwest to northeast coast of Puerto Rico, including
Culebra.

.Days Two through Seven...Friday through Wednesday

High moisture content and favorable upper level conditions will enhance
showers and thunderstorm development across the forecast area through
the end of the work week and into the weekend. This expected activity
will lead to urban and small stream flooding and ponding of water on
roadways each day. The potential for mudslides in areas of steep terrain
is also probable, as well as in areas that have been affected by recent
heavy rains due to the loose and saturated soil. Tropical Cyclone Kirk
or its remnants is still forecast to move south of the islands by late
Friday through Saturday, increasing the potential for heavy rainfall
with enhanced shower and thunderstorm activity. A gradual improvement
and lesser activity is expected for Sunday and into the early part of
next week. Also, Tropical Cyclone Kirk will increase seas across
the eastern and southern waters of the islands as early as Friday
afternoon.

A large long period north-northeast swell is forecast to enter
the Atlantic waters between late Thursday night into Friday
morning and spread across the regional waters through the weekend.
This swell will generate hazardous seas as well as dangerous large
breaking waves across the northern and east facing beaches of the
islands. Life threatening rip currents, beach erosion and minor
coastal flooding are possible with this swell event, mainly
across the northern beaches of Puerto Rico and the U.S. Virgin
Islands.

.Spotter information statement...

Widespread spotter activation is not anticipated, however individual
spotter are encouraged to report high winds, flooding and rip
currents to the National Weather Service in San Juan.
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Re: Caribbean - Central America Weather

#19597 Postby cycloneye » Thu Sep 27, 2018 4:59 pm

FLASH FLOOD WATCH
National Weather Service San Juan PR
415 PM AST Thu Sep 27 2018

...Flash flood is possible from Friday evening to Saturday evening...

.Tropical cyclone Kirk will pass to the south of the local
islands, but periods of heavy rainfall are expected across the
U.S. Virgin Islands and eastern Puerto Rico from Friday night
into Saturday.

PRZ001>007-012-013-VIZ001-002-281000-
/O.NEW.TJSJ.FF.A.0003.180928T2200Z-180930T0000Z/
/00000.0.ER.000000T0000Z.000000T0000Z.000000T0000Z.OO/
San Juan and Vicinity-Northeast-Southeast-Eastern Interior-
North Central-Central Interior-Ponce and Vicinity-Culebra-Vieques-
St.Thomas...St. John...and Adjacent Islands-St Croix-
Including the cities of Bayamon, Carolina, Catano, Guaynabo,
San Juan, Toa Alta, Toa Baja, Trujillo Alto, Ceiba, Canovanas,
Fajardo, Humacao, Loiza, Luquillo, Naguabo, Rio Grande, Arroyo,
Guayama, Maunabo, Patillas, Salinas, Yabucoa, Aguas Buenas,
Caguas, Cayey, Cidra, Comerio, Gurabo, Juncos, Las Piedras,
San Lorenzo, Arecibo, Barceloneta, Dorado, Florida, Manati,
Vega Alta, Vega Baja, Aibonito, Baranquitas, Ciales, Coamo,
Corozal, Jayuya, Morovis, Naranjito, Orocovis, Villalba,
Guayanilla, Juana Diaz, Yauco, Penuelas, Ponce, Santa Isabel,
Culebra, Vieques, Anna`s Retreat, Charlotte Amalie,
Charlotte Amalie East, Charlotte Amalie West, Cruz Bay,
Christiansted, Frederiksted, Frederiksted Southeast,
and Grove Place
415 PM AST Thu Sep 27 2018

...FLASH FLOOD WATCH IN EFFECT FROM FRIDAY EVENING THROUGH
SATURDAY EVENING...

The National Weather Service in San Juan has issued a

* Flash Flood Watch for portions of Puerto Rico and Virgin
Islands, including the following areas, in Puerto Rico,
Central Interior, Culebra, Eastern Interior, North Central,
Northeast, Ponce and Vicinity, San Juan and Vicinity,
Southeast, and Vieques. In Virgin Islands, St Croix and
St.Thomas...St. John...and Adjacent Islands.

* From Friday evening through Saturday evening.

* There is a high risk for flash flooding across the eastern half of
Puerto Rico as well as the U.S. Virgin Islands as Kirk...which is
expected to be a Tropical Depression...moves south of the area
Friday night into Saturday morning.

Although Kirk is expected to weaken to a tropical depression, its
associated moisture combined with favorable upper level dynamics
will increase the risk for flooding and mudslides across the local
islands, particularly across south, southeast and eastern Puerto
Rico as well as Saint Croix, Friday night through at least
Saturday night.

Rainfall totals will range between 2 to 4 inches with higher amounts
near 6 inches. Soils are already saturated across some areas with
rivers and small streams running near or above normal. Therfore, a
Flash Flood Watch will be in effect for the eastern Half of Puerto
Rico as well as US Virgin Islands Friday evening through
Saturday evening.

Lower rainfall accumulations are expected across western Puerto
Rico with rainfall totals ranging between 1 and 2 inches with
isolated amounts near 3 inches. As a result, the confidence for
flash flooding is lower across western Puerto Rico, however there
is still a potential for urban and small stream flooding.

PRECAUTIONARY/PREPAREDNESS ACTIONS...

A Flash Flood Watch means that conditions may develop that lead
to flash flooding. Flash flooding is a very dangerous situation.

You should monitor later forecasts and be prepared to take action
should Flash Flood Warnings be issued.
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Re: Caribbean - Central America Weather

#19598 Postby cycloneye » Fri Sep 28, 2018 5:10 am

Area Forecast Discussion
National Weather Service San Juan PR
553 AM AST Fri Sep 28 2018

.SYNOPSIS...The combination of favorable upper level dynamics and
the lingering moisture will continue to result in rainy conditions
across the region. Expect passing showers across the eastern half
portion of Puerto Rico and the U.S. Virgin Islands during the
morning hours followed by afternoon convection across the interior
and western sections of Puerto Rico by this afternoon. Tropical
Storm Kirk is forecast to degenerate into a Tropical Depression.
Although the National Hurricane Center forecast keep it as a
tropical cyclone for the next 24 hours, it could dissipate much
earlier. Despite the system will move well south of the islands,
its associated moisture combined with a TUTT-low will result in a
wet and unstable weather pattern late this afternoon into
Saturday.

&&

.SHORT TERM...Today through Sunday...
An upper level trough, located to the west northwest of the local
islands, will continue to support shower and thunderstorm
development through the weekend. Due to the presence of high
moisture content, streamer-like showers and thunderstorms are
expected to move across the local waters into portions of the
eastern half of Puerto Rico, the U.S. Virgin Islands and local
waters. Although this activity is expected to diminish by mid
morning, much deeper moisture associated to what is now Tropical
Storm Kirk will begin to move into the forecast area by this
afternoon. Local orographic effects along with favorable upper
level conditions will favor significant shower and thunderstorm
development through Saturday, particularly over portions of
eastern and southern Puerto Rico, Vieques, Culebra and the U.S.
Virgin Islands. For that reason, a Flash Flood Watch will be in
effect from this evening through Saturday evening. On Sunday,
showers and thunderstorm are expected across the forecast area as
lingering moisture associated to Kirk remains across the local
area. The strongest activity is expected over the waters in the
morning and across portions of the interior and western Puerto
Rico in the afternoon.

In addition to the weather conditions, the marine and surf zone
conditions are expected to significantly deteriorate as a result of
Kirk`s passage across the region, but also due to a long period
northerly swell that will invade the local waters today through the
weekend. As a result, a High Surf Advisory and Coastal Flood Watch
will be in effect starting at 6 AM AST this morning and 6 PM AST
this afternoon, respectively. Both products will continue through
the weekend.

.LONG TERM...Monday through Saturday...
Model guidance are suggesting a wet and unstable weather pattern
through much of the upcoming week. Although upper level support is
forecast to become less favorable through at least mid-week,
plenty of tropical moisture will continue over the region. This
moisture will be enough to combined with local effects and diurnal
heating which could result in afternoon convection across most of
the islands each day.

The latest model guidance continues to indicate Post-Tropical
Cyclone Leslie meandering across the north-central Atlantic
Ocean through much of the upcoming week. As Leslie meanders and
strengthens, feeding bands will transport tropical moisture from
the Caribbean Sea and into the local area under a southwestward
wind flow. Under this weather pattern, unsettled weather
conditions will be possible across the forecast area. If model
guidance are correct, the peak of the event will be Thursday
afternoon-Saturday as a tropical wave moves in and interacts with
this plume of tropical moisture and with another TUTT-low, which
is forecast to amplify aloft. Model have been consistence with
this solution, however the confidence is low-moderate given how
far the event is from now, and because it is attached to the
evolution of Post-Tropical Cyclone Leslie.

&&

.AVIATION...
VCSH expected across most of the terminal sites through the
morning, except for TJSJ with -SHRA/VCTS and TJBQ/TJMZ with no
weather expected. As TS Kirk approaches the local area, SHRA/VCTS
with brief MVRF conditions are expected across all terminal sites.
First at TNCM/TKPK at around 28/10z, then at TIST/TISX at around
28/14z, and the rest of the terminals by 28/16z. This conditions
will prevail throughout the rest of the forecast period. Surface
winds will continue from the E to NE at 5 to 15 knots knots with
higher gusts up to 30 knots possible.

&&

.MARINE...
Hazardous marine conditions associated to a long period
northeasterly swell will continue across the Atlantic and
Caribbean Waters and the Anegada Passage. By late this afternoon,
the combination of seas from Kirk and this swell will cause
hazardous seas and dangerous surf zone conditions across most of
the local waters and coastal areas, respectively. Small craft
advisories are in effect across most of the local waters. Please,
mariners should see the Coastal Waters Forecast for more details
on deteriorating weather conditions.

&&

.PRELIMINARY POINT TEMPS/POPS...
SJU 88 77 86 75 / 90 90 90 50
STT 90 79 85 77 / 90 90 90 60
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Re: Caribbean - Central America Weather

#19599 Postby cycloneye » Sat Sep 29, 2018 5:15 am

Area Forecast Discussion
National Weather Service San Juan PR
538 AM AST Sat Sep 29 2018

.SYNOPSIS...
Kirk has degenerate into an open wave, and its remnants are
forecast to move westward well south of the local islands.
However, its moisture is forecast to increase the potential for
widespread showers across the islands throughout the day. A large
northeast swell previously generated by Sub-tropical Storm Leslie
will impact the Atlantic and Caribbean Waters as well as the
local Passages. These swell will cause life threatening surf and
rip currents, as well beach erosion and coastal flooding.

&&

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

The strong tropical wave which was once Tropical Storm Kirk and
the associated large moisture field will continue moving westward
and south of the islands throughout the day. However, deep
tropical moisture trailing the wave will continue to lift
northwards and spread across the forecast area to maintain a very
moist and unstable environment through at least early Sunday.
Enhanced showers and thunderstorm activity with gusty winds and
areas of heavy rainfall and dangerous lightning will therefore
continue to affect the regional waters, the U.S. Virgin Islands
and the east and southern portions of Puerto Rico during the rest
of the morning hours. Cloudiness and showers activity is then
expected to spread across the rest of Puerto Rico throughout the
day. Occasional breaks in cloud cover along with local and diurnal
effects, good low level moisture convergence and instability
aloft will lead to enhanced afternoon convection over the western
and northern portions of Puerto Rico including the San Juan Metro.
This will lead to periods of heavy rains and possibly strong
thunderstorms in isolated areas. Although the Tutt low and
associated trough will continue to shift westwards during the day
as the ridge builds aloft, there will still be sufficient
instability and ventilation aloft to support afternoon convection
across the islands. For this reason the Flash Flood Watch will
remain in effect through this evening.

By Monday a gradual erosion of moisture is expected across the
area with a somewhat drier airmass and decreasing easterly trade
winds. However, locally and diurnally induced afternoon convection
will remain possible across portions of the islands.

.LONG TERM....Monday through Sunday...
Today, model guidance are indicating less moisture and
instability across the region through at least mid-week.
Although upper level support is forecast to become less
favorable through at least mid-week, the available tropical
moisture will be enough to combined with local effects and
diurnal heating which could result in afternoon convection across
portions of the islands each day.

A trough is forecast to amplify and move near the region
increasing upper level dynamics after mid-week. In addition,
model guidance continues to suggest plenty of tropical moisture
associated with another active tropical wave by Thursday or
Friday. Then a surface low pressure system is forecast to develop
across the Caribbean and lift northward across the region by the
upcoming weekend. Model guidance have some discrepancy of the
location and timing of the event, for that reason the confidence
still low-moderate given how far the event is from now.

&&

.AVIATION...
Prevailing VFR with brief MVFR due to SHRA/VCTS
accompanying a tropical wave/remnants of Kirk moving across the
forecast area til at least 29/22z. SCT-BKN lyrs nr FL025...
FL040...FL090 and BKN-OVC nr FL250. Mtn top obscr interior sections
of PR due to low cig and SHRA. Tempo MVFR with SHRA/TSRA. Sfc wnds
light and variable bcmg east to southeast at 10 to 15 kts with
higher gusts aft 29/14z.

&&

.MARINE...
41043 and 41044 reported swell of 12.5 ft at 17 sec from the NE
and 17 ft at 19 sec from the NE, respectively. These swell will
cause life-threatening surf and rip currents across the Atlantic
Coastal areas. Coastal Flood Advisory and High Surf Advisory are
in effect for the north and east facing beaches of Puerto Rico
and the U.S. Virgin Islands.

The seas across the Caribbean Waters are deteriorating. Ponce Buoy
(42085) showed an increasing trend, and seas already surpass 6
feet. The seas are forecast to increase at 6 to 8 feet across the
Caribbean Waters and at 8 to 10 feet with occasional seas up to 13
feet across the Caribbean Offshore waters.

Small craft advisory is in effect for all the local waters except
for the Coastal Waters of southwestern Puerto Rico where small
craft operators are urge to exercise caution due to seas at 4 to 6
feet and winds between 15 and 20 knots. Hazardous marine
conditions will continue through at least early next week.

Another northeast swell are expected to return by late Wednesday
night into Thursday to create 7 foot seas or higher.

&&

.PRELIMINARY POINT TEMPS/POPS...
SJU 88 76 88 78 / 80 50 60 40
STT 89 79 88 78 / 70 60 60 50
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Re: Caribbean - Central America Weather

#19600 Postby cycloneye » Sun Sep 30, 2018 5:19 am

Area Forecast Discussion
National Weather Service San Juan PR
530 AM AST Sun Sep 30 2018


.SYNOPSIS...
A long period northeast swell is creating hazardous marine and
coastal conditions along the waters and coastlines of the Atlantic
Ocean of Puerto Rico and the U.S. Virgin Islands. This swell will
cause life threatening surf and rip currents, as well beach
erosion and coastal flooding. The trailing moisture associated
with the remnants of Kirk will continue to produce shower and
thunderstorm activity across the Caribbean Waters and some
passing showers across the eastern half portion of Puerto Rico and
the U.S. Virgin Islands through the morning hours. Then, the
available moisture combined with diurnal heating and local
effects will result in afternoon convection across the Northwest
Quadrant of Puerto Rico and in the San Juan Metro Area.

&&

.SHORT TERM...Today through Tuesday...
Trailing moisture and mid to upper level cloud debris from the
departed tropical wave that was once Kirk will linger across
region during most of the day. Mid to upper level ridge will
continue to build across the region today through Tuesday
gradually favoring stable conditions aloft. However still lots of
residual moisture across the region, and the expected break in
high level cloud cover later in the morning and during the
afternoon hours will lead to locally and diurnally induced
afternoon convection across portions of the islands. Latest
observations, along with radar and satellite imagery and recent
VAD wind profile, all suggest a light southeast steering wind
flow across the region today. That said, expect afternoon shower
and thunderstorms to develop mainly over parts of the interior and
northwest to north sections of Puerto Rico. Some of this activity
may later affect parts of the San Juan metro area during the
afternoon. Lesser activity expected across the U.S. Virgin Islands
today but there is still a change for isolated to scattered
afternoon showers and possibly isolated thunderstorms during the
rest of the day.

By Monday through Tuesday, gradual erosion of moisture transport
is forecast across the area with a somewhat drier airmass and
diminishing easterly trade winds. However, locally and diurnally
induced afternoon convection will remain possible across the
islands each afternoon but no widespread rainfall is expected.

.LONG TERM...Wednesday through Monday...
Model guidance are suggesting a somewhat drier air mass and more
stable weather pattern through at least early Thursday. Although
upper level support is forecast to become less favorable through
at least mid-week, the available tropical moisture will be enough
to combined with local effects and diurnal heating which could
result in afternoon convection across portions of the islands each
day.

Another tropical wave is forecast to reach the northeast Caribbean
Sea by Thursday or Friday. In addition, a polar trough is
forecast to amplify and move near the region increasing upper
level support through at least Saturday. Among that, model
guidance continues to suggest a surface low pressure system which
is forecast to develop across the Caribbean and lift northward
across the region by the upcoming weekend. Discrepancies continues
associated with the location and timing of the event, for that
reason the confidence still low-moderate, however a wet and
unstable weather patterns seems to be possible by the end of this
week. By Sunday, a mid to upper level ridge is forecast to build
over the northeast Caribbean.


&&

.AVIATION...
VFR...brief MVFR SHRA/TSRA mainly ovr coastal waters and
en route btw islands til 30/14z. Tropical wave/remnants of Kirk
moving across the eastern Caribbean creating convective debris clds
with SCT-BKN lyrs nr FL025... FL050...FL100 and BKN-OVC btw FL200-
FL250. Mtn top obscr interior sections of PR due to low cig and
SHRA. Tempo MVFR with SHRA/TSRA. Sfc wnds calm to lgt/vrb bcmg east
to southeast at 5 to 15 kts with higher gusts aft 30/14z. l/lvl wnds
fm E-SE 10-15 kts blo FL250.

&&

.MARINE...
Hazardous marine conditions continues across the Atlantic Waters,
Caribbean Offshore waters and local passages as a long period
northeasterly swell will gradually diminish throughout the day.
San Juan Buoy (41053) reported significant wave heights between 10
and 9 feet with a wave period between 15 and 17 seconds during the
last five hours. This swell is capable of producing breaking wave
heights between 14 and 19 feet. This swell is forecast to
gradually diminish throughout the day, but hazardous marine
conditions will continue through at least early Monday morning.
This swell will cause life-threatening surf and rip currents
across the Atlantic Coastal areas. Coastal Flood Advisory and High
Surf Warnings are in effect for the north and east facing beaches
of Puerto Rico and High Surf Advisory is in effect for the
north/east facing beaches of the U.S. Virgin Islands.

In addition, a Small craft Advisory is in effect for most of the
local waters except across the Southwest coastal waters and
Caribbean Coastal waters of Puerto Rico. But small craft operators
are urge to exercise caution due to seas up to 6 feet.

Small craft advisory is in effect for all the local waters except
for the Coastal Waters of Southwest PR and the Caribbean Coastal
waters of Puerto Rico where small craft operators are urge to
exercise caution due to seas at 4 to 6 feet. Hazardous marine
conditions will continue through at least Monday morning.

Another northeast swell are expected to return by late Wednesday
into Thursday to create 7 foot seas or higher.

&&

.PRELIMINARY POINT TEMPS/POPS...
SJU 88 77 89 77 / 50 30 40 30
STT 88 78 89 77 / 50 50 50 40

&&
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