Upper Level Low 18N 64W just east of PR

[underthwx]

Is the ULL drifting towards the North a little?...hard for me to tell when watching the loop...



The posts in this forum are NOT official forecast and should not be used as such. They are just the opinion of the poster and may or may not be backed by sound meteorological data. They are NOT endorsed by any professional institution or storm2k.org. For official information, please refer to the NHC and NWS products.

[underthwx]

NWS San Juan:



LATEST SATELLITE IMAGES THIS MORNING DEPICTED AN UPPER LEVEL TUTT
LOW...JUST EAST NORTHEAST OF PUERTO RICO AND THE U.S. VIRGIN
ISLANDS. THIS TUTT LOW AND ITS ASSOCIATED LOW LEVEL REFLECTIONS OR
PERTURBATIONS ARE EXPECTED TO PROPAGATE WEST TO WEST NORTHWEST THIS
AFTERNOON AND TONIGHT...APPROACHING TO THE REGION TOMORROW. THIS
FEATURE IS EXPECTED TO PRODUCE AN INCREASE IN CLOUDINESS...SHOWERS
AND THUNDERSTORMS ACROSS THE LOCAL ISLANDS SATURDAY AFTERNOON AND
SUNDAY. THE PROXIMITY OF THIS FEATURE TO THE REGION WILL DESTABILIZE
THE ATMOSPHERE PRODUCING A GOOD DEAL OF CLOUDINESS...SHOWERS AND
THUNDERSTORMS ACROSS THE LOCAL ISLANDS FOR AT LEAST THE FIRST PART
OF THE UPCOMING WORK WEEK. ONLY MINOR CHANGES WERE DONE TO THE
PREVIOUS FORECAST PACKAGE.



The posts in this forum are NOT official forecast and should not be used as such. They are just the opinion of the poster and may or may not be backed by sound meteorological data. They are NOT endorsed by any professional institution or storm2k.org. For official information, please refer to the NHC and NWS products.

[underthwx]

FARTHER
TO THE EAST...AN UPPER LEVEL LOW IS CENTERED OVER THE LEEWARD
ISLANDS NEAR 18N62W AND HAS CONTINUED TO SLOWLY DRIFT WESTWARD.
SOUTHWESTERLY MIDDLE TO UPPER LEVEL FLOW IS ADVECTING MOISTURE
NORTHWARD FROM THE INTERTROPICAL CONVERGENCE ZONE BETWEEN
54W-64W AND IS GENERATING WIDELY SCATTERED SHOWERS AND ISOLATED
TSTMS OVER PORTIONS OF THE WINDWARD ISLANDS AND SE CARIBBEAN S
OF 14N E OF 66W. CLOSER NEAR THE CENTER OF THE UPPER LOW...
ISOLATED SHOWERS AND TSTMS ARE N OF 18N BETWEEN 61W-64W.


NHC 2PM Discussion excerpt...

[underthwx]

Most of the global model guidance have backed way off on the forecast of development in the western Caribbean next week. I think given the forecast pattern that the western Caribbean needs to be monitored for possible tropical development over the next 6 to 10 days. It’s interesting to note that the ensemble guidance members of the European and GFS models forecast lowering pressures in the western part of the Caribbean starting around Tuesday or Wednesday and continuing through next Sunday.


The posts in this forum are NOT official forecast and should not be used as such. They are just the opinion of the poster and may or may not be backed by sound meteorological data. They are NOT endorsed by any professional institution or storm2k.org. For official information, please refer to the NHC and NWS products.

[underthwx]

AREA FORECAST DISCUSSION FOR THE FLORIDA KEYS
NATIONAL WEATHER SERVICE KEY WEST FL
300 PM EDT FRI SEP 16 2011


T TERM...TONIGHT THROUGH MONDAY...ANY REMNANTS OF THE UPPER
TROUGH WILL LIFT OUT QUICKLY TONIGHT. STRONGER...NEAR 590 DM RIDGING
AT 500 MB WILL BUILD IN BACK ACROSS FLORIDA AND THE FLORIDA KEYS
FROM THE WEST AND REMAIN IN PLACE THROUGH MONDAY. AT THE SURFACE AND
IN THE LOWER LEVELS...AN INVERTED TROUGH/WEAK TROPICAL WAVE NOW
LOCATED OVER THE CENTRAL BAHAMAS WILL CONTINUE TO MOVE TOWARDS THE
KEYS TONIGHT THROUGH SATURDAY NIGHT. BOTH 12Z NAM AND GFS MODEL
FORECAST SOUNDINGS CONTINUE TO ILLUSTRATE VERY DRY AIR WILL REMAIN
IN PLACE ABOVE 850 MB THROUGH SATURDAY NIGHT...WITH PWAT
(PRECIPITABLE WATER) REMAINING BETWEEN 1.25 AND 1.50 INCHES THROUGH
12Z SUNDAY. SKIES WILL REMAIN MOSTLY CLEAR TONIGHT ACROSS THE
ISLANDS AND MOSTLY SUNNY DURING THE DAY ON SATURDAY. THE MORE
COMFORTABLE CONDITIONS WILL SLOWLY ERODE ON SATURDAY NIGHT DUE TO
INCREASING HUMIDITY.

FOR SUNDAY THRU MONDAY...THE DEEPER MOISTURE AHEAD OF THE INVERTED
TROUGH IS PROGGED REACH THE KEYS AND ADJOINING WATERS...WITH THE
TROUGH MOVING SLOWLY ACROSS SUNDAY...SUNDAY NIGHT...AND WEST OF THE
KEYS ON MONDAY. NO SURPRISINGLY...BOTH THE GFS AND ECMWF ILLUSTRATE
PWAT INCREASING TO AROUND OR ABOVE 2.00 INCHES FOR THE SUNDAY
THROUGH MONDAY PERIODS. GIVEN ELEVATED LARGE SCALE LIFT AND
ASSOCIATED LOWER LEVEL CONVERGENCE IN THE BOUNDARY LAYER..POPS WERE
INCREASE BACK CLOSE TO CLIMATOLOGY ON SATURDAY NIGHT (40%)...AND
THEN ABOVE NORMAL AGAIN...A GOOD CHANCE (50%) FOR SHOWERS AND
THUNDERSTORMS BOTH ON SUNDAY AND SUNDAY NIGHT...WITH POPS AT 40
PERCENT FOR MONDAY.

ALSO...THE COMBINATION OF A 1030 MB RIDGE ANCHORED OVER THE
NORTHEASTERN UNITED STATES WITH THE APPROACHING INVERTED TROUGH WILL
ALLOW FOR A SLIGHT INCREASE IN LOCAL WINDS BEGINNING SATURDAY NIGHT
AND CONTINUING THROUGH THE REST OF THE WEEKEND AS WELL AS ON MONDAY.
GIVEN THE GRADIENT...EXPECTING GENTLE TO MODERATE BREEZES OVER THE
KEYS...EXCEPT MODERATE TO FRESH BREEZES ARE EXPECTED ACROSS THE
ATLANTIC WATERS.

EXTENDED...MONDAY NIGHT THROUGH FRIDAY...NEAR 590 DM RIDGING AT 500
MB WILL HOLD IN PLACE THROUGH THE WEEK...BUT THE LAST WEEK OF SUMMER
WILL SEE A RETURN TO MORE TYPICAL MOISTURE...HUMIDITY AND RAIN
CHANCES. THE SURFACE RIDGING WILL REMAIN ACROSS CENTRAL FLORIDA
WHILE SEVERAL FORECAST MODELS ARE INDICATING TYPICAL SIGNALS FOR
DEVELOPMENT LOWER PRESSURES AREA ACROSS THE WESTERN CARIBBEAN SEA.
SO WHILE EXACT TIMING AND PLACEMENT OF ANY OF THESE FEATURES IS
STILL HIGHLY UNCERTAIN...AN INCREASE IN LOCAL WINDS DUE TO A
PRESSURE GRADIENT BETWEEN LOWER PRESSURE IN THE CARRIBEAN SEA AND
HIGHER PRESSURE OVER THE FLORIDA PENINSULA...WILL RESULT IN EXPECT
GENTLE TO MODERATE EAST BREEZES ACCOMPANIED BY AMPLE AVAILABLE
MOISTURE IN THE SURFACE TO 500 MB LAYER...WITH GFS FORECAST
SOUNDINGS ILLUSTRATING PWAT NEAR/AROUND 2.00 INCHES THROUGH THE
ENTIRE WEEK. AS SUCH...WILL BE MAINTAINING MIDDLE OF THE ROAD CHANCE
POPS THROUGH THE PERIOD. THE GFS IS ALSO TIMING ANOTHER
WAVE/INVERTED TROUGH AXIS MOVING ACROSS THE AREA WEDNESDAY THROUGH
FRIDAY. SO WILL WAIT AND SEE IF THIS FEATURE CONTINUES TO SHOW UP
BEFORE INCREASING LOCAL RAIN CHANCES LATER NEXT WEEK ACROSS THE KEYS.



The posts in this forum are NOT official forecast and should not be used as such. They are just the opinion of the poster and may or may not be backed by sound meteorological data. They are NOT endorsed by any professional institution or storm2k.org. For official information, please refer to the NHC and NWS products.

[Hylian Auree]

Yeah no, not much going to happen with this.

[Raininfyr]

Last post was Friday, so no one is probably reading this. However, this ULL has been very persistent, Sunday morning, and you can still see the spinning. The west side of the Low is naked, but the northeast, southeast side is producing rain. Shear perhaps?

[Jimsot]

I wish it would go away or dissipate. We have had according to our rain gage about three inches of rain since yesterday from the storms that keep forming and moving over Anguilla. We have had enough!

[cycloneye]

I wish it would go away or dissipate. We have had according to our rain gage about three inches of rain since yesterday from the storms that keep forming and moving over Anguilla. We have had enough!

We have a Caribbean thread where the members who live in the islands post the observations or news about weather,so when you can,stop by and post the weather from Anguilla.

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