Caribbean - Central America Weather

[msbee]

Current 94L computer models

[Gustywind]

8 AM Tropical Discussion

000
AXNT20 KNHC 171134
TWDAT

TROPICAL WEATHER DISCUSSION
NWS NATIONAL HURRICANE CENTER MIAMI FL
805 AM EDT FRI AUG 17 2012

TROPICAL WEATHER DISCUSSION FOR NORTH AMERICA...CENTRAL
AMERICA...GULF OF MEXICO...CARIBBEAN SEA...NORTHERN SECTIONS
OF SOUTH AMERICA...AND ATLANTIC OCEAN TO THE AFRICAN COAST
FROM THE EQUATOR TO 32N. THE FOLLOWING INFORMATION IS BASED
ON SATELLITE IMAGERY...WEATHER OBSERVATIONS...RADAR...AND
METEOROLOGICAL ANALYSIS.

BASED ON 0600 UTC SURFACE ANALYSIS AND SATELLITE IMAGERY
THROUGH 1115 UTC.


THE MOST RECENT RAWINSONDE DATA FOR BAMAKO IN MALI SHOW
THAT A TROPICAL WAVE HAS PASSED THAT STATION DURING THE LAST
48 HOURS OR SO. CURRENT SATELLITE IMAGERY AND OTHER OBSERVATIONS
SUGGEST A COMPARATIVELY LOWER AMPLITUDE TROPICAL WAVE THAT IS
ALONG 17W TO THE SOUTH OF 12N. NUMEROUS STRONG CONVECTIVE
PRECIPITATION IS FROM 8N TO 13N BETWEEN 22W AND 27W.
THIS PRECIPITATION ALSO IS IN THE MONSOON TROUGH.

[cycloneye]

This morning's discussion of 94L by Dr Jeff Masters.

94L developing off the coast of Africa

A large tropical wave emerged from the coast of Africa Thursday night, and was designated Invest 94L by NHC this Friday morning. The models have been very gung-ho on this system, and develop it into a tropical storm by the middle of next week. 94L will follow a west to west-northwest track over the next week, and may threaten the northern Lesser Antilles Islands as early as Friday, August 24. This storm could eventually affect Bermuda, the U.S. East Coast, or Canada 10 - 14 days from now, but could also recurve harmlessly out to sea well before reaching the Lesser Antilles, as suggested by the 00 UTC run of the GFS model. In their 8 am EDT Tropical Weather Outlook, NHC gave 94L a 10% chance of developing into a tropical depression by Sunday morning.

[cycloneye]

The canadian model is too close for confort.



http://moe.met.fsu.edu/cgi-bin/cmctc2.c ... =Animation

[msbee]

Update from Rob at Crown Weather. He thinks 94L could threaten NE Caribbean next week

http://www.crownweather.com/?p=7069

[cycloneye]

AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE SAN JUAN PR
323 PM AST FRI AUG 17 2012

.SYNOPSIS...A TROPICAL WAVE WILL CONTINUE MOVING WEST ACROSS THE
LOCAL AREA TONIGHT THROUGH EARLY SATURDAY AND THEN AWAY FROM THE
REGION LATER SATURDAY AND SUNDAY. TUTT WILL RE-ALIGN WEST THROUGH
NORTH OF THE REGION SUNDAY THROUGH TUESDAY. A SECOND TROPICAL WAVE
IS EXPECTED TO AFFECT THE LOCAL AREA TUESDAY NIGHT THROUGH
WEDNESDAY.

&&

.DISCUSSION...THE TROPICAL WAVE AND ITS ASSOCIATED MOISTURE WILL
CONTINUE TO INTERACT WITH FAVORABLE MID TO UPPER LEVEL CONDITIONS
AND LOCAL EFFECTS TONIGHT THROUGH AT LEAST THE FIRST PART AND
PROBABLY MOST OF SATURDAY...RESULTING IN SOME CLOUDINESS AND BANDS
OF SHOWERS AND THUNDERSTORMS WITH LOCALLY HEAVY RAINFALL AND GUSTY
WINDS ACROSS THE LOCAL ISLANDS. A DRIER AND MORE STABLE AIR MASS
WITH SAHARAN DUST WILL BEGIN TO ENCOMPASS THE LOCAL AREA SATURDAY
NIGHT WITH EVEN DRIER CONDITIONS EXPECTED FOR SUNDAY AND MONDAY.
THAT SAID...THERE WILL STILL BE LOCALIZED CONVECTION EACH
AFTERNOON.

THEREAFTER...A SECOND TROPICAL WAVE IS EXPECTED TO AFFECT THE
LOCAL AREA TUESDAY NIGHT THROUGH WEDNESDAY...PROBABLY RESULTING IN
ADDITIONAL CLOUDINESS...SHOWERS AND THUNDERSTORMS ACROSS THE
ISLANDS. LOOKING WAY AHEAD...WE WILL CONTINUE TO CLOSELY MONITOR
INVEST 94L.

&&

.AVIATION...SHRA/TSRA ASSOCIATED WITH A TROPICAL WAVE WILL CONTINUE
TO AFFECT THE FORECAST AREA THROUGH AT LEAST THIS EVENING. AS A
RESULT...MVRF/IFR CONDS ARE POSSIBLE IN PASSING SHRA/TSRA...ACROSS
TJMZ AND TJBQ THROUGH AT LEAST 17/22Z. ALSO...MOUNTAIN OBSCURATION
CONTINUES ACROSS THE INTERIOR SECTIONS OF PUERTO RICO TONIGHT.
WINDS WILL BE MAINLY FROM THE EAST AT AROUND 15 KTS THROUGH
TONIGHT...VEERING TO THE EAST-SOUTHEAST LATE TONIGHT AND
SATURDAY.

&&

.MARINE...GENERALLY EXPECT WINDS OF 17 KNOTS OR LESS AND SEAS OF 5
FEET OR LESS ACROSS THE REGIONAL WATERS THROUGH AT LEAST SUNDAY.

&&

.PRELIMINARY POINT TEMPS/POPS...
SJU 79 88 80 88 / 40 40 40 30
STT 79 90 81 90 / 30 30 50 20

[cycloneye]

Looks like a huge threat to the islands

18z GFS goes further west with this system and is a real danger to the Eastern Caribbean islands if it pans out.

[cycloneye]

This is this evening's discussion about 94L by Dr Jeff Masters.

94L a potential threat to the Lesser Antilles
A large tropical wave emerged from the coast of Africa Thursday night, and was designated Invest 94L by NHC this Friday morning. The models have been impressed this system, and develop it into a tropical storm by the middle of next week. The latest set of 12Z (8 am EDT) model runs are divided on how far west 94L will make it before curving more to the northwest. The ECMWF model keeps 94L weak for the next 5 - 6 days, and has progressively been bringing the storm closer to the Lesser Antilles Islands with each successive run. The ECMWF predicts 94L will pass very close to the northern Lesser Antilles August 24 - 25 as a weak tropical storm. The 12Z GFS model predicted recurvature of 94L well to the east of the Lesser Antilles and Bermuda, but the latest 18Z run has the storm plowing through the Lesser Antilles on Thursday, August 23, as a strong tropical storm, then becoming a hurricane in the Eastern Caribbean. Given that our two top models for forecasting hurricane tracks are increasingly showing a threat to the Lesser Antilles, residents of the islands should pay close attention to the progress of 94L. The eventual track of 94L will depend on the strength of the storm over the next seven days, which is difficult to forecast, since 94L will have the usual trouble with dry air to the north from the Saharan Air Layer (SAL.) With the models changing their tune drastically from run to run, its tough to say what land areas might be most at risk from the storm in the long term. In their 2 pm EDT Tropical Weather Outlook, NHC gave 94L a 10% chance of developing into a tropical depression by Sunday afternoon.

[cycloneye]

8 PM Tropical Weather Outlook Up to 20%

AN AREA OF DISTURBED WEATHER ASSOCIATED WITH A TROPICAL WAVE IS
LOCATED WELL SOUTH OF THE CAPE VERDE ISLANDS. SOME SLOW DEVELOPMENT
IS POSSIBLE DURING THE NEXT FEW DAYS AS THIS SYSTEM MOVES TOWARD
THE WEST AT 15 TO 20 MPH. THIS SYSTEM HAS A LOW CHANCE...20
PERCENT...OF BECOMING A TROPICAL CYCLONE DURING THE NEXT 48 HOURS.

[Gustywind]

8 PM Tropical Weather Discussion

TROPICAL WAVE EXTENDS FROM 11N24W TO 17N21W MOVING W AT 15-20
KT. THE WAVE IS EMBEDDED WITHIN AN EASTERN ATLC MONSOON GYRE
FOCUSED AROUND A 1009 MB LOW CENTERED NEAR 11N24W. TOTAL
PRECIPITABLE WATER IMAGERY INDICATES DEEP LAYER MOISTURE IN THE
VICINITY OF THE WAVE FROM 08N-15N BETWEEN 18W-24W WITH ISOLATED
MODERATE CONVECTION OCCURRING WITHIN 180 NM EITHER SIDE OF THE
WAVE AXIS.

[cycloneye]

Good morning. We keep watching invest 94L.



AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE SAN JUAN PR
506 AM AST SAT AUG 18 2012

.SYNOPSIS...AT UPPER LEVELS...TROUGHINESS WILL CONTINUE NORTH AND
NORTHWEST OF THE LOCAL AREA THROUGH TUESDAY. THEN HIGH PRESSURE
WILL BUILD MID WEEK AND CONTINUE THROUGH AT LEAST FRIDAY.

AT MID LEVELS...HIGH PRESSURE REMAINS TO THE NORTH THROUGH THE
PERIOD. A TROUGH JUST EAST OF 50 WEST TODAY WILL MOVE THROUGH THE
AREA ON TUESDAY. HEIGHTS BEGIN TO DROP AGAIN ON THURSDAY.

AT LOWER LEVELS...A TROPICAL WAVE IS MOVING THROUGH THE CARIBBEAN
TODAY AND WILL PASS OUT OF THE AREA TONIGHT. DRIER AIR WILL THEN
PASS JUST NORTH OF PUERTO RICO AND THE U.S. VIRGIN ISLANDS...WITH
MOISTURE PATCHES PASSING THROUGH FROM TIME TO TIME. ANOTHER
TROPICAL WAVE WILL MOVE THROUGH ON TUESDAY NIGHT FOLLOWED BY DRIER
AIR ON THURSDAY AND THURSDAY NIGHT.

&&

.DISCUSSION...STRONG SHOWERS AND THUNDERSTORMS HAVE DEVELOPED IN
THE CARIBBEAN AND ARE MOVING WEST NORTHWEST THROUGH THE WATERS
SOUTH OF PUERTO RICO. THESE ARE ASSOCIATED WITH THE TROPICAL WAVE
THAT HAS BEEN PASSING MAINLY TO THE SOUTH. ONLY A FEW SHOWERS HAVE
DEVELOPED OVER LAND SO FAR BUT MORE ARE EXPECTED AT THE DAY
PROGRESSES. SOME LOCAL URBAN AND SMALL STREAM FLOODING IS
EXPECTED...MAINLY IN THE INTERIOR AND NORTHWEST TODAY. ALTHOUGH
DRIER AIR IS EXPECTED BEHIND THIS WAVE...THE GFS BRINGS MOIST AIR
BACK OVER PUERTO RICO AND THE U.S. VIRGIN ISLANDS ALMOST RIGHT
AWAY SUNDAY NIGHT AND MONDAY WITH THE DRIEST AIR REMAINING TO THE
NORTH OF EVERYONE. ANOTHER TROPICAL WAVE CONTINUES TO BE FORECAST
TO PASS THROUGH ON TUESDAY NIGHT WITH SHOWERS AND THUNDERSTORMS.
THIS MEANS THAT A CHANCE OF SHOWERS WILL CONTINUE FOR MUCH OF THE
FORECAST AREA SUNDAY AND MONDAY...BECOMING QUITE LIKELY TUESDAY
AND WEDNESDAY. DRIER AIR ALSO FOLLOWS THIS WAVE...BUT HOW DRY WILL
DEPEND ON WHAT THE NEXT WAVE CONTAINS AND ITS PATH.

THE ELEPHANT IN THE KITCHEN...SO TO SPEAK...IS THE GFS FORECAST OF A
HURRICANE PASSING BETWEEN CULEBRA AND SAINT THOMAS LATE SATURDAY.
THIS CAUSES NORTHEAST FLOW AT THE SURFACE TO BEGIN THURSDAY AND
STRENGTHEN FRIDAY AND SATURDAY. ENSEMBLE SOLUTIONS SHOW A WIDE
RANGE OF TRACKS AND THE GFS LIKELY HAS NOT STABILIZED SUFFICIENTLY.
THE GFS TRACK SOLUTION WAS WELL TO THE NORTHEAST OF THE ISLANDS 24
HOURS AGO AND THE 18Z RUN SHOWED THE STORM PASSING TO THE SOUTH A
LITTLE EARLIER...BUT AM UNABLE TO LOAD MOST OF THE PARAMETERS FROM
THIS...18/00Z...MODEL FORECAST PACKAGE DUE TO THE UNCERTAINTY YET IN THE
FORECAST AND THE SEVERITY OF THE CONDITIONS FORECAST...EVEN FOR A
SYNOPTIC SCALE MODEL. SOME CHANGE TO THE TRACK IS LIKELY AND IT IS
IMPOSSIBLE TO TELL IF THIS WOULD TAKE THE CYCLONE NORTH OR SOUTH
OF THE AREA...ALTHOUGH FORMATION IN THE NEXT 72 HOURS SEEMS MORE
LIKELY THAN IT WAS YESTERDAY. THEREFORE WILL SIMPLY SAY THAT THIS
SOLUTION IS PLAUSIBLE AND PRELIMINARY SEASONAL PREPARATIONS SHOULD
BE COMPLETED AND DOUBLE CHECKED...BUT NO CONFIDENCE CAN BE GIVEN
TO THE CLOSE-PASSAGE SCENARIO YET.

&&

.AVIATION...
MAINLY VFR CONDITIONS EXPECTED FOR THE LOCAL TAF SITES
OVERNIGHT WITH TEMPO MVFR OVER TJPS BETWEEN 18/09Z AND 18/11Z DUE TO
APPROACHING SHRA/TSRA. A PASSING TROPICAL WAVE WILL CAUSE AFTERNOON
SHOWERS AND THUNDERSTORMS ACROSS THE CORDILLERA CENTRAL AND WESTERN
PUERTO RICO RESULTING IN MVFR/IFR CONDITIONS AT TJMZ/TJBQ AS WELL AS
AND MOUNTAIN OBSCURATIONS. WINDS WILL BE MAINLY FROM THE EAST SOUTH
EAST AT AROUND 10 KTS WITH HIGHER GUSTS AS WELL AS SEA BREEZE
VARIATIONS AFTER 18/13Z.

&&

.MARINE...SEAS REMAIN BELOW 6 FEET FOR THE PRESENT...BUT LOCAL
SEAS COULD EXCEED 7 FEET IN SQUALLS AND THUNDERSTORMS TODAY.
THEN QUIETER CONDITIONS ARE EXPECTED THROUGH TUESDAY. MARINERS
PLANNING EXTENDED TRIPS INTO THE AREA SHOULD STAY ABREAST OF
CONDITIONS EXPECTED FRIDAY THROUGH SUNDAY OF NEXT WEEK.

&&

.PRELIMINARY POINT TEMPS/POPS...
SJU 88 80 89 80 / 40 50 30 30
STT 89 80 90 80 / 40 50 20 20

[cycloneye]

This morning's discussion of 94L by Rob of Crown Weather.

http://www.crownweather.com/?page_id=4557

Invest 94L:
Invest 94L, a tropical wave which is located about 250 miles or so to the southwest of the Cape Verde Islands, is of significant concern to me and I will say that right up front. Latest analysis early this morning shows that shower and thunderstorm activity is gradually becoming more consolidated and is slowly increasing. Additionally, the 850 millibar vorticity chart shows that the amount of spin associated with 94L is also slowly increasing.

Invest 94L is currently tracking to the west at a forward speed of 15 to 20 mph and I expect this westward track to continue right into a majority of next week. As for strengthening, I think we will see gradual intensification and this system seems destined to become Tropical Storm Isaac by either Sunday night or during the day Monday. Beyond that, environmental conditions are favorable for strengthening throughout much of next week and I do feel confident enough to say that I think this will become a hurricane by about the middle part of next week.

The latest GFS model guidance has shifted further west with the overall track of 94L and forecasts it to significantly impact Barbados and much of the Lesser Antilles with hurricane conditions from Thursday afternoon through Thursday night and into Friday morning. After that, the GFS model forecasts future Isaac to impact Puerto Rico with hurricane conditions by next Saturday. From there, the longer range GFS model seems to suggest a track north and then northeast about halfway between the US East Coast and Bermuda during the week of August 27th.

The latest European model guidance has a much weaker system that never really closes off into a storm. This leads to a Caribbean cruiser by late next week into next weekend. Right now, given the presentation of how 94L looks and that the overall pattern in the Atlantic Basin is favorable for an intensifying tropical cyclone, I think the European model guidance forecast seems unlikely and I’m leaning much more towards the stronger GFS model forecast.

So, here are my thoughts on Invest 94L: I do think that this system poses an eventual threat to the Lesser Antilles. Given the fact that the ridge of high pressure to the north of 94L is fairly strong, I see no evidence of a turn to the northwest before it reaches the Lesser Antilles. Additionally, the fact that the intensity guidance is insistent on significant strengthening to not only hurricane strength, but major hurricane strength leads me to believe that all interests in the Lesser Antilles, as well as Barbados should closely monitor the progress of this system for you may have a hurricane knocking on your door by Thursday.

Needless to say, I will be monitoring Invest 94L closely and will keep you all updated.

[cycloneye]

8 AM Tropical Weather Outlook up to 40%

SHOWER AND THUNDERSTORM ACTIVITY CONTINUES IN ASSOCIATION WITH A
TROPICAL WAVE LOCATED A COUPLE HUNDRED MILES SOUTHWEST OF THE CAPE
VERDE ISLANDS. CONDITIONS APPEAR CONDUCIVE FOR GRADUAL DEVELOPMENT
DURING THE NEXT FEW DAYS...AND THIS SYSTEM HAS A MEDIUM CHANCE...40
PERCENT...OF BECOMING A TROPICAL CYCLONE DURING THE NEXT 48 HOURS
AS IT MOVES WESTWARD AT 15 TO 20 MPH.

[Gustywind]

8 AM Tropical Weather Discussion

A TROPICAL WAVE IS LOCATED IN THE ERN ATLC EXTENDING FROM 18N23W
TO A 1008 MB LOW NEAR 12N27W...EMBEDDED WITHIN THE MONSOON GYRE
DESCRIBED BELOW. SCATTERED SHOWERS AND THUNDERSTORMS ARE FROM
11N-15N BETWEEN 26W-31W...WITHIN THE BROAD CONVECTIVE REGION
ASSOCIATED TO THE MONSOON TROUGH. CONDITIONS APPEAR CONDUCIVE
FOR GRADUAL DEVELOPMENT DURING THE NEXT FEW DAYS...AND THIS
SYSTEM HAS A MEDIUM CHANCE OF BECOMING A TROPICAL CYCLONE DURING
THE NEXT 48 HOURS...AS IT MOVES WESTWARD AT 15 TO 20 MPH.

[Gustywind]

Concerning 94L here is an interresting snippet from our Pro Mets of Meteo-France Guadeloupe (latest weather forecast 4AM) see below. Looks like they're pretty confident on a thing : a cyclonic feature should cross somewhere, maybe enough close the Leewards.
I'm a bit surprised, because of honestly it's pretty rare to read so early athing like that from Meteo France... while 94L is (for the moment) far away from the Carib islands.

Those who live in the Eastern Carib should stay vigilant during the next couple of days.

Trend for Wednesday August 22 and Thursday 23 August:
"Wednesday and Thursday, the proximity of a cyclonic phenomenon could result in a perturbed weather, with probably heavy rains, and a strengthening of the wind and swell, which may also take unusual directions. The path and the strength of this phenomenon are still very uncertain, also keep you well informed about the weather forecast next week"!

[cycloneye]

This mornings discussion of 94L by Dr Jeff Masters.

Posted by: Dr. Jeff Masters, 11:24 AM AST on August 18, 2012 +0

A large tropical wave that emerged from the coast of Africa Thursday night (Invest 94L) is located a few hundred miles southwest of the Cape Verde Islands off the coast of Africa, and is headed west at 15 - 20 mph. This storm is a threat to develop into a tropical storm that will affect the Lesser Antilles Islands as early as Wednesday. The storm is under moderate wind shear of 10 - 20 knots, and is over waters of 27.5°C. A large area of dry air lies just to the north of 94L, as seen on the latest Saharan Air Layer (SAL) analysis. This morning's 8:15 am EDT ASCAT pass caught the east side of 94L, and showed a partial surface circulation. Satellite images show just a modest amount of heavy thunderstorm activity, and I expect the earliest that 94L could develop into a tropical depression would be Sunday.

Forecast for 94L

The latest 8 am EDT run of the SHIPS model predicts that wind shear will be low, 5 - 10 knots, and ocean temperatures will gradually warm from 27.5°C to 28.5°C over the next four days, as 94L tracks westwards towards the Lesser Antilles. As is typical with storms making the crossing from Africa to the Antilles, dry air to the north will likely interfere with development. However, with shear expected to be low, dry air may be less of an issue for 94L than it was for Ernesto or TD 7. The storm should maintain a nearly due west track through Monday night, to a point near 50°W, about 700 miles east of the Lesser Antilles. At that point, a trough of low pressure passing to the north of 94L may be able to pull the storm more to the northwest, as suggested by the latest 06Z (2 am EDT) run of the NOGAPS model, and by three members of the GFS model ensemble forecast (Figure 2.) However, the models have been trending more towards a solution where this trough is not strong enough to influence 94L's path. This scenario will be more likely if 94L takes its time to develop, since a weaker storm will be smaller and shallower, and less likely to respond to the trough passing to the north. Our two best performing models, the GFS and ECMFW, both take 94L through the Lesser Antilles. The ECMWF, which predicts that 94L will stay weak and not develop, is faster, bringing the storm through the Lesser Antilles on Wednesday. The GFS model is slower, bringing 94L to the Lesser Antilles on Thursday as a strong tropical storm. The models have shown poor run-to-run consistency in both the timing and the track of 94L, so it is difficult to assess which land areas might be most at risk, and when. A database of historical probabilities of storms in the same location as 94L maintained by Dr. Bob Hart of Florida State University reveals that historically, 45% of storms in this location have eventually hit land, with Canada (13% chance) and North Carolina (15% chance) the most likely targets. In their 8 am EDT Tropical Weather Outlook, NHC gave 94L a 40% chance of developing into a tropical depression by Monday morning.

[cycloneye]

Up to 50%.

A TROPICAL WAVE LOCATED ABOUT 300 MILES WEST OF THE CAPE VERDE
ISLANDS CONTINUES TO PRODUCE DISORGANIZED SHOWER AND THUNDERSTORM
ACTIVITY. ENVIRONMENTAL CONDITIONS APPEAR CONDUCIVE FOR GRADUAL
DEVELOPMENT DURING THE NEXT FEW DAYS...AND THIS SYSTEM HAS A MEDIUM
CHANCE...50 PERCENT...OF BECOMING A TROPICAL CYCLONE DURING THE
NEXT 48 HOURS AS IT MOVES WESTWARD AT ABOUT 20 MPH.

[Jimsot]

This is from weatherwunderground extended online forecast fro Anguilla Friday 24th. How can they be so certain this far out?

Friday Night
Mostly cloudy with thunderstorms. Low of 81F with a heat index of 91F. Winds from the East at 65 to 80 mph. Chance of rain 80% with rainfall amounts near 5.2 in possible.

[cycloneye]

AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE SAN JUAN PR
302 PM AST SAT AUG 18 2012

.SYNOPSIS...WEAK UPPER TROUGHS REMAIN NORTH AND NORTHWEST OF THE
LOCAL AREA THROUGH TUESDAY. DRIER AIR AND SAHARAN DUST WILL MOVE
ACROSS PUERTO RICO AND THE U.S. VIRGIN ISLANDS. THE TROPICAL WAVE
WILL APPROACH TO THE LOCAL AREA ON TUESDAY NIGHT.

&&

.DISCUSSION...MOISTURE LEFT BEHIND BY THE DEPARTING TROPICAL WAVE
COMBINED WITH A WEAK UPPER TROUGH WEST OF THE FORECAST AREA TO
PRODUCE SHOWERS AND THUNDERSTORMS ACROSS THE SOUTHWESTERN PUERTO
RICO THIS MORNING AS WELL AS ACROSS THE CARIBBEAN WATERS AND THE
MONA PASSAGE. MOIST AND UNSTABLE CONDITIONS WILL PREVAIL ACROSS
THE FORECAST AREA AT LEAST UNTIL LATE TONIGHT...AND MAY RESULT IN
LATE AFTERNOON SHOWERS ACROSS THE INTERIOR AND NORTHWEST SECTIONS
OF PUERTO RICO. AN OVERALL DRY AND MORE STABLE AIR MASS WILL
MOVE INTO THE LOCAL AREA SUNDAY MORNING...LIMITING THE SHOWER
ACTIVITY ACROSS THE LOCAL ISLANDS THROUGH AT LEAST EARLY TUESDAY.
SAHARAN DUST WILL ACCOMPANY THIS DRIER AIR MASS...RESULTING IN
HAZY SKIES. THE NEXT TROPICAL WAVE AND ITS ASSOCIATED MOISTURE AND
INSTABILITY WILL MOVE ACROSS THE EASTERN CARIBBEAN TUESDAY NIGHT
THROUGH WEDNESDAY MORNING. ALTHOUGH...THE BULK OF THE MOISTURE IS
EXPECTED TO PASS JUST SOUTH OF THE LOCAL AREA...SCATTERED SHOWERS
AND A FEW THUNDERSTORMS ARE POSSIBLE DURING THIS PERIOD.

MEDIUM TO LONG RANGE...THE NHC IS MONITORING A VIGOROUS TROPICAL
WAVE LOCATED ABOUT 300 MILES WEST OF THE CAPE VERDE ISLANDS.
ENVIRONMENTAL CONDITIONS APPEAR CONDUCIVE FOR GRADUAL DEVELOPMENT
DURING THE NEXT FEW DAYS. OPERATIONAL MODELS SUGGEST THAT THIS
DISTURBANCE WILL APPROACH THE LOCAL REGION BETWEEN FRIDAY AND
SATURDAY NEXT WEEK. AS A RESULT...WE SHOULD CLOSELY MONITOR THE
PROGRESS OF THIS SYSTEM DURING THE NEXT SEVERAL DAYS...AS WE APPROACH
THE PEAK OF THE HURRICANE SEASON. PLEASE REFER TO TROPICAL WEATHER
OUTLOOK FOR MORE DETAILS.

&&

.AVIATION...CONT VFR XCP CHC OF MVFR CIG/VSBY AT TJMZ/TJBQ LATE THIS
AFTERNOON IN SHRA/TSRA. MOST LWR CONDS WILL BE INLAND OVER NW
MAINLAND PR BUT WL ONLY LAST 3 HRS OR SO. LLVL WIND SE 20-25 KT TO
FL150 BCMG E 15-25 KT BY SUNDAY MORNING. USVI TO BE VFR WITH STRAY
SHRA MAINLY OVR WATER.

&&

.MARINE...TRANQUIL MARINE CONDITIONS EXPECTED THROUGH AT LEAST
EARLY NEXT WEEK. SEAS WILL RANGE BETWEEN 2 AND 4 FEET ACROSS MOST
OF THE LOCAL WATERS...WITH 5 FEET EXPECTED ONLY ACROSS THE
OFFSHORE ATLANTIC WATERS.

&&

.PRELIMINARY POINT TEMPS/POPS...
SJU 79 90 79 91 / 40 30 30 30
STT 79 90 80 90 / 40 20 20 20

[msbee]

This is from weatherwunderground extended online forecast fro Anguilla Friday 24th. How can they be so certain this far out?

Friday Night
Mostly cloudy with thunderstorms. Low of 81F with a heat index of 91F. Winds from the East at 65 to 80 mph. Chance of rain 80% with rainfall amounts near 5.2 in possible.

that's unreliable of course. It's all still very uncertain. Still we have to watch out for this one.
just checked for St. Maarten.
looks like we have the same forecast.
Friday Night
Mostly cloudy with thunderstorms. Low of 81F with a heat index of 91F. Winds from the ENE at 55 to 80 mph. Chance of rain 80% with rainfall amounts near 4.0 in. possible.