Caribbean - Central America Weather

[cycloneye]

AREA FORECAST DISCUSSION...UPDATED
NATIONAL WEATHER SERVICE SAN JUAN PR
1012 AM AST SAT SEP 17 2011

.UPDATE...POTENTIALLY ACTIVE AFTERNOON AS TUTT AND ITS SFC
REFLECTION CONTINUE TO MOVE WEST WITH INCREASING FORCING TO
GENERATE STRONG TO POSSIBLY SEVERE CONVECTION THIS AFTERNOON.
LATEST VISIBLE IMAGERY SHOWS CU FIELD STARTING TO DEVELOP ACROSS
THE CORDILLERA WHERE NAM12 SHOWS BEST SFC CONVERGENCE PER NEGATIVE
VALUES IN ITS SFC DIVERGENCE FIELD. BETTER MOISTURE AND
INSTABILITY TODAY THAN YESTERDAY SO CONVECTION SHOULD BE MORE WIDESPREAD.
0-6 KM WINDS ARE MORE FROM THE EAST TODAY SUGGESTING CONVECTION
WILL MOVE TO WRN PR AS OPPOSED TO THE SOUTHWEST LIKE IT DID
YESTERDAY. SOME TSTMS ACROSS THE ATLC COASTAL WATERS HAVE HAD
OVERSHOOTING TOPS INDICATIVE OF HOW UNSTABLE AIR MASS ALREADY IS.
MID-LVL TEMPS ARE SIMILAR TO YDAY SO THREAT FOR HAIL AND DOWNBURST
WINDS STILL THERE. CURR FCST HAS GOOD HANDLE ON EXPECTED WX. NO
PLANS TO UPDATE FCST ATTM.

[underthwx]

Is it possible there may be a invest assigned to the Western Caribbean over the weekend???...

[cycloneye]

Is it possible there may be a invest assigned to the Western Caribbean over the weekend???...

If a low pressure starts to take shape,even if is broad,maybe.

[Gustywind]

- Barbados

http://stormcarib.com/reports/current/barbados.shtml

•By "PEQUENEZA,J" <sydmouth at caribsurf.com>
•Date: Sat, 17 Sep 2011 06:02:25 -0400

We just keep having more and more rain. Three days straight. The ground is absolutely saturated. During the night lots of thunder and lightening and the wind and the rain lashing through. My back garden hollow is flooded to the highest point I have seen in many years. Haven't heard any news yet but there has to be lots of flooding across Barbados this morning. Supposedly this to continue for another day!

[chrisjslucia]

We've had occasional heavy rain over the past two days but this morning was exceptionally heavy, with thunderstorms directly overhead. Lots of localised flooding I suspect without any clear indication of how the weather will fare over the next 24 hours. Now, it has cleared up but the weather to our East continues to look stormy. They're half way through constructing a new road past here and, wow, has that taken a hammering this morning.

[underthwx]

What is the shear currently over the caribbean???...and also what are the forecasted shear like over the next couple of days???..can someone
show a scatterometer of the Carribean???...

[cycloneye]

What is the shear currently over the caribbean???...and also what are the forecasted shear like over the next couple of days???..can someone
show a scatterometer of the Carribean???...

Shear looks to be light to moderate,so not detrimental right now.

[cycloneye]

TROPICAL WEATHER OUTLOOK
NWS NATIONAL HURRICANE CENTER MIAMI FL
200 PM EDT SAT SEP 17 2011

FOR THE NORTH ATLANTIC...CARIBBEAN SEA AND THE GULF OF MEXICO...

AN ELONGATED AREA OF LOW PRESSURE EXTENDING A FEW HUNDRED MILES
SOUTH AND SOUTHWEST OF THE CAPE VERDE ISLANDS IS PRODUCING
DISORGANIZED SHOWERS AND THUNDERSTORMS. SOME SLOW DEVELOPMENT OF
THIS SYSTEM IS POSSIBLE DURING THE NEXT COUPLE OF DAYS AS IT MOVES
WESTWARD AT 10 TO 15 MPH. THIS SYSTEM HAS A LOW CHANCE...20
PERCENT...OF BECOMING A TROPICAL CYCLONE DURING THE NEXT 48 HOURS.

ELSEWHERE...TROPICAL CYCLONE FORMATION IS NOT EXPECTED DURING THE
NEXT 48 HOURS.

$$
FORECASTER CANGIALOSI

[cycloneye]

FLOOD ADVISORY
NATIONAL WEATHER SERVICE SAN JUAN PR
111 PM AST SAT SEP 17 2011

PRC011-083-099-131-172015-
/O.NEW.TJSJ.FA.Y.0453.110917T1711Z-110917T2015Z/
/00000.N.ER.000000T0000Z.000000T0000Z.000000T0000Z.OO/
ANASCO PR-MOCA PR-SAN SEBASTIAN PR-LAS MARIAS PR-
111 PM AST SAT SEP 17 2011

THE NATIONAL WEATHER SERVICE IN SAN JUAN HAS ISSUED AN

* URBAN AND SMALL STREAM FLOOD ADVISORY
FOR THE FOLLOWING MUNICIPALITIES...

IN PUERTO RICO
ANASCO...MOCA...SAN SEBASTIAN AND LAS MARIAS

* UNTIL 415 PM AST

* AT 109 PM AST...DOPPLER RADAR INDICATED SHOWERS AND THUNDERSTORMS
WITH VERY HEAVY RAIN ALONG THE SAN SEBASTIAN AND LAS MARIAS COUNTY
LINE MOVING SLOWLY TO THE WEST AROUND 5 MPH. THESE THUNDERSTORMS
WILL BE CAPABLE OF PRODUCING TWO TO FOUR INCHES OF RAIN PER HOUR
AND CAUSE FLOODING OF SMALL STREAMS AND POOR DRAINAGE AREAS.

MOST FLOOD DEATHS OCCUR IN AUTOMOBILES. NEVER DRIVE YOUR VEHICLE INTO
AREAS WHERE THE WATER COVERS THE ROADWAY. FLOOD WATERS ARE USUALLY
DEEPER THAN THEY APPEAR. JUST ONE FOOT OF FLOWING WATER IS POWERFUL
ENOUGH TO SWEEP VEHICLES OFF THE ROAD. WHEN ENCOUNTERING FLOODED
ROADS MAKE THE SMART CHOICE...TURN AROUND...DONT DROWN.

&&

LAT...LON 1839 6703 1838 6694 1839 6692 1836 6689
1823 6691 1819 6690 1821 6697 1820 6702
1825 6706 1825 6713 1830 6723 1831 6713
1841 6712 1846 6706

$$

ROSA
--------------------------------------------------------------------------------

[cycloneye]

FLOOD ADVISORY
NATIONAL WEATHER SERVICE SAN JUAN PR
253 PM AST SAT SEP 17 2011

PRC051-143-145-172145-
/O.NEW.TJSJ.FA.Y.0454.110917T1853Z-110917T2145Z/
/00000.N.ER.000000T0000Z.000000T0000Z.000000T0000Z.OO/
VEGA ALTA PR-VEGA BAJA PR-DORADO PR-
253 PM AST SAT SEP 17 2011

THE NATIONAL WEATHER SERVICE IN SAN JUAN HAS ISSUED AN

* URBAN AND SMALL STREAM FLOOD ADVISORY
FOR THE FOLLOWING MUNICIPALITIES...

IN PUERTO RICO
VEGA ALTA...VEGA BAJA AND DORADO

* UNTIL 545 PM AST

* AT 251 PM AST...DOPPLER RADAR INDICATED SHOWERS AND THUNDERSTORMS
WITH VERY HEAVY RAIN AND EVEN POSSIBLY SOME SMALL HAIL ACROSS DORADO
DRIFTING NORTHWEST. THESE THUNDERSTORMS WILL BE CAPABLE OF PRODUCING
FLOODING OF SMALL STREAMS...URBAN AND POOR DRAINAGE AREAS.

MOST FLOOD DEATHS OCCUR IN AUTOMOBILES. NEVER DRIVE YOUR VEHICLE INTO
AREAS WHERE THE WATER COVERS THE ROADWAY. FLOOD WATERS ARE USUALLY
DEEPER THAN THEY APPEAR. JUST ONE FOOT OF FLOWING WATER IS POWERFUL
ENOUGH TO SWEEP VEHICLES OFF THE ROAD. WHEN ENCOUNTERING FLOODED
ROADS MAKE THE SMART CHOICE...TURN AROUND...DONT DROWN.

&&

LAT...LON 1849 6636 1849 6633 1849 6630 1846 6629
1840 6631 1843 6642 1849 6644 1851 6641

$$

ROSA

[underthwx]

http://www.cpc.ncep.noaa.gov/products/p ... h_full.png

Graphic Depicting Tropical Development Areas...

[underthwx]

http://www.cpc.ncep.noaa.gov/products/p ... h_full.png

Graphic Depicting Tropical Development Outlook.

[cycloneye]

AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE SAN JUAN PR
252 PM AST SAT SEP 17 2011

.SYNOPSIS...A TUTT LOW WILL CONTINUE TO LINGER ACROSS
THE LOCAL AREA FOR THE REST OF TODAY AND INTO TOMORROW MORNING...IT
WILL THEN LIFT NORTH ON SUNDAY THROUGH MONDAY. ITS LOW TO MID
LEVEL REFLECTIONS WILL CONTINUE MOVING WEST ACROSS THE LOCAL
ISLANDS TODAY THROUGH TONIGHT OR EARLY SUNDAY...THEN SLOWLY MOVE
AWAY FROM THE LOCAL AREA LATER SUNDAY THROUGH MONDAY AND TUESDAY.


&&

.DISCUSSION...THE INCREASE IN MOISTURE AND INSTABILITY HELPED
DEVELOP THUNDERSTORMS IN THE INTERIOR...WESTERN...NORTH CENTRAL...AND
NORTHWESTERN SECTIONS OF PUERTO RICO WITH A SOUTHEAST WIND. THE
CENTER OF THE TUTT LOW SEEMS TO BE RIGHT OVER THE AREA AND MODELS
ARE SUGGESTING THAT THE TUTT WILL LINGER OVER THE AREA UNTIL EARLY
SUNDAY. AT THAT TIME...THE TUTT SHOULD START LIFTING AND MOVING
NORTH.

FORECAST SOUNDINGS SUGGEST THAT PW VALUES AND INSTABILITY WILL
INCREASE ON SUNDAY...GIVING US A BETTER CHANCE OF THUNDERSTORMS
ACROSS THE AREA...ESPECIALLY ACROSS THE NORTHWEST QUADRANT OF
PUERTO RICO. HOWEVER...THE FORECAST SOUNDINGS ALSO SUGGEST THAT
THE UPPER LEVEL JET CURRENTLY OVER THE AREA WILL WEAKEN AND WE
WILL BE LEFT WITH A MUCH LIGHTER WIND ALOFT FROM THE WEST. THE U.S.
VIRGIN ISLANDS AND ACROSS THE LOCAL WATERS...EXPECT SCATTERED SHOWERS
AND AN ISOLATED THUNDERSTORM OR TWO...BUT THE LOCAL EFFECTS OF
PUERTO RICO MAY HAVE A LOT TO DO WITH THE DEVELOPMENT OF
THUNDERSTORMS.


&&

.AVIATION...TSTMS LIKELY AT JMZ LATER TODAY WITH MVFR/IFR CIGS.
ELSEWHERE...CHANCES FOR TSRA INCREASE TONIGHT ACROSS LEEWARDS AND
USVI TERMINALS WITH MORE WIDESPREAD CONVECTION TOMORROW LIKELY
AFFECTING JSJ/JBQ...USVI AND LEEWARD ISLANDS TERMINALS.

&&

.PRELIMINARY POINT TEMPS/POPS...
SJU 87 76 87 76 / 50 50 50 50
STT 86 77 88 78 / 40 60 60 50

[cycloneye]

http://www.cpc.ncep.noaa.gov/products/precip/CWlink/ghazards/images/gth_full.png

Graphic Depicting Tropical Development Outlook.

Here is the text from that.

Last Updated: 09.13.11 Valid: 09.14.11 - 09.27.11

There is a lot of spread amongst the dynamical model MJO index forecasts during the upcoming 1-2 week period. A few models indicate some eastward propagation of a weak signal during Week-2. Based on recent observations and the high degree of uncertainty with the MJO index model forecasts, the MJO is forecast to remain weak during the period. The MJO is not expected to contribute substantially to anomalous tropical convection across the global tropics during the period at this time.

During Week-1, an enhanced monsoon flow is expected to enhance rainfall in northern India, the Bay of Bengal, and Southeast Asia. Above average sea surface temperatures are likely to enhance rainfall in the western equatorial Indian Ocean. Lower tropospheric convergence over central Africa is expected to enhance rainfall in the region, while a ridge of high pressure and anomalous northerly flow is expected to suppress convection in north-central Mexico.

A high chance of tropical cyclone development exists in the northwest Pacific as tropical depression 18W is forecast to intensify to a tropical storm. Behind this system is another disturbance that has a moderate chance of developing into a tropical cyclone since upper level conditions are favorable for development at this time. A broad area of low pressure in the western Caribbean Sea is expected to bring widespread precipitation to the region and Central America. A tropical wave in the eastern Atlantic increases the threat for tropical cyclone development in the region.

During week-2, signals are rather weak for anomalous convection across the global tropics. However, monsoon flow is expected to remain enhanced across the Bay of Bengal and parts of Southeast Asia. Model guidance and above average sea surface temperatures also favor enhanced convection in the western Indian Ocean. Moderate chances for tropical cyclone development are expected in the main development region of the eastern tropical Atlantic as robust easterly waves continue to exit Africa. There is a moderate chance of tropical cyclone development in the western Caribbean Sea associated with a broad area of low pressure, forecast low wind shear, and warm sea surface temperatures.

[underthwx]

The convection in the Western Caribbean persists..and thus should be closely monitored...(also over the Bahamas)...


Only my opinion..please refer to the NHC or your local NWS for official forecasts.

[underthwx]

NWS Key West AFD...

AS IS TYPICALLY THE CASE AT THIS TIME OF YEAR...BROAD LOWER PRESSURE
OVER THE NORTH CENTRAL AND WESTERN CARIBBEAN SEA WILL KEEP A
DEEPENING MODERATE TO OCCASIONALLY FRESH EASTERLY FLOW PATTERN IN
PLACE WITH THE BOUNDARY LAYER ACROSS THE ISLANDS THROUGH THE
UPCOMING WEEK...WITH BOTH 12Z NAM AND GFS MODEL FORECAST SOUNDINGS
ILLUSTRATING PWAT (PRECIPITABLE WATER) REMAINING AROUND 2.00 INCHES
TUESDAY THROUGH SATURDAY. BOTH THE GFS AND ECMWF CONTINUE WITH
INDICATIONS THAT THE NEXT TROPICAL WAVE/INVERTED TROUGH AND
ASSOCIATED DEEPER MOISTURE SHOULD MOVE ACROSS THE KEYS THURSDAY
THROUGH SATURDAY. FOR NOW WILL CONTINUE TO MAINTAIN MIDDLE OF THE
ROAD CHANCE FOR POPS UNTIL THE TIMING CAN BE HONED IN WITH EVEN
GREATER CLARITY. BUT OUR RAIN CHANCES WILL CONTINUE TO BE SLIGHTLY
ABOVE NORMAL THROUGH THE PERIOD...AT 40 PERCENT EACH PERIOD.

[underthwx]

Latest still Rainbow Image:


http://www.ssd.noaa.gov/goes/east/carb/rb-l.jpg

[cycloneye]

I saw this web cam from St Barts and thought it was a beautiful shot to post it here. Look at the rainbow to the left.



Saved image by ImageShack.us

[underthwx]

now that is a rainbow image...

[cycloneye]

FLOOD ADVISORY
NATIONAL WEATHER SERVICE SAN JUAN PR
547 PM AST SAT SEP 17 2011

PRC051-143-145-180045-
/O.NEW.TJSJ.FA.Y.0455.110917T2147Z-110918T0045Z/
/00000.N.ER.000000T0000Z.000000T0000Z.000000T0000Z.OO/
VEGA ALTA PR-VEGA BAJA PR-DORADO PR-
547 PM AST SAT SEP 17 2011

THE NATIONAL WEATHER SERVICE IN SAN JUAN HAS ISSUED AN

* URBAN AND SMALL STREAM FLOOD ADVISORY FOR MINOR FLOODING OF POOR
DRAINAGE AREAS IN
FOR THE FOLLOWING MUNICIPALITIES...

IN PUERTO RICO
VEGA ALTA...VEGA BAJA AND DORADO

* UNTIL 845 PM AST

THE DIRECTOR OF EMERGENCY MANAGEMENT IN VEGA ALTA REPORTED THAT ROAD
620 IN FATIMA AND ROAD 647 ALSO IN VEGA ALTA IS FLOODED DUE TO A
RISE IN THE CIBUCO RIVER.

MOST FLOOD DEATHS OCCUR IN AUTOMOBILES. NEVER DRIVE YOUR VEHICLE INTO
AREAS WHERE THE WATER COVERS THE ROADWAY. FLOOD WATERS ARE USUALLY
DEEPER THAN THEY APPEAR. JUST ONE FOOT OF FLOWING WATER IS POWERFUL
ENOUGH TO SWEEP VEHICLES OFF THE ROAD. WHEN ENCOUNTERING FLOODED
ROADS MAKE THE SMART CHOICE...TURN AROUND...DONT DROWN.

&&

LAT...LON 1849 6636 1848 6630 1846 6629 1840 6631
1837 6634 1843 6642 1849 6644 1851 6641

$$

SNELL
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