Flash Flood Warning 183, NWS JSJ

AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE SAN JUAN PR
330 PM AST SAT OCT 22 2005

.SYNOPSIS...AT UPPER LEVELS...HIGH PRESSURE NORTH OF THE MONA
CHANNEL WILL MOVE NORTHEAST INTO THE MID ATLANTIC BY MID WEEK AND
THEN STRETCH BACK AND BUILD NORTH OF PUERTO RICO. A LOW PRESSURE IN
THE ATLANTIC EAST OF THE WINDWARD ISLANDS WILL DIG SOUTHWEST TO
SOUTH OF THE WINDWARD ISLANDS ON MONDAY AND MOVE NORTHWEST TO THE
CARIBBEAN WELL SOUTH OF HAITI BY WEDNESDAY. LOW PRESSURE THEN
RETURNS TO THE WINDWARD ISLANDS FROM THE NORTHEAST OVER THE
FOLLOWING WEEKEND PUSHING THE HIGH NORTHWARD.

AT MID LEVELS...HIGH PRESSURE WILL CONTINUE IN THE ATLANTIC
NORTHEAST OF PUERTO RICO THROUGH THE FORECAST PERIOD. A RIDGE
EXTENDING ACROSS PUERTO RICO FROM THIS HIGH ON SUNDAY WILL ROTATE
OVER CUBA BY WEDNESDAY AND THEN VARY LITTLE THROUGH THE BEGINNING OF
THE FOLLOWING WEEK.

AT LOWER LEVELS...TROPICAL DEPRESSION 25 CONTINUES TO STRENGTHEN IN
THE CARIBBEAN. AT 2 PM IT WAS ABOUT 179 MILES SOUTHWEST OF PONCE. IT
WILL MOVE THROUGH THE DOMINICAN REPUBLIC TONIGHT AND THEN TOWARD THE
BAHAMAS...THEN MOVE NORTH...EVENTUALLY GETTING ABSORBED IN A COLD
FRONT MOVING OFF THE COAST OF THE EASTERN UNITED STATES. A WEAK WAVE
WILL MOVE THROUGH THE AREA WEDNESDAY NIGHT AND AGAIN FRIDAY NIGHT
AND SATURDAY.

&&

.DISCUSSION...TROPICAL DEPRESSION 25 IS JUST OUTSIDE RADAR RANGE
SUCH THAT ONLY THE BANDS IN ITS NORTHEAST QUADRANT ARE VISIBLE...
NEVERTHELESS A CLEAR ROTATION CAN BE SEEN IN BOTH RADAR AND
SATELLITE IMAGERY. SMALLER SQUALL LINES ARE ROTATING AROUND THE
SYSTEM AND COMING ONSHORE ALONG PUERTO RICOS SOUTHERN COAST. MOST OF
THE SHOWERS THAT DO SO ARE WEAKENING CONSIDERABLY AND THINNING OUT
BEFORE REACHING THE NORTHERN COAST...SO PRECIP AMOUNTS FROM THESE
SHOWERS IS FAIRLY LIGHT AND BEST ON THE SOUTHERN COASTAL PLAINS AND
FOOTHILLS. MAXIMUM TEMPERATURES HAVE BEEN LITTLE AFFECTED
CONSIDERING THE INCREASED CLOUD COVER AND ADDITIONAL RAIN SHOWERS.
STRONGER WINDS HAVE ALLOWED THE VIRGIN ISLANDS TO REMAIN A LITTLE
COOLER DURING THE DAY HOWEVER. FORECAST TEMPERATURES WILL SEE A
LITTLE INFLUENCE FROM SOUTHEASTERLY FLOW FOR THE NEXT SEVERAL
DAYS...JUST ENOUGH TO COUNTERACT THE CLOUD COVER ON THE NORTH
COAST...THOUGH TEMPERATURES ON THE SOUTH COAST SHOULD BE COOLER THAN
AVERAGE.

AS THE SYSTEM CONTINUES TO MOVE WEST NORTHWEST...MODELS
SHOW THE MOISTURE AT 850 MB OVER PUERTO RICO DECREASING SLOWLY AFTER
00Z SUNDAY...ALTHOUGH SOME BANDING OF RELATIVE HUMIDITY IN THE
FORECAST SOLUTION OVER PUERTO RICO AT 18Z STRETCHES FROM SOUTH
SOUTHEAST TO NORTH NORTHWEST JUST WEST OF SAINT CROIX...OVER VIEQUES
AND CENTRAL PUERTO RICO AND WILL BE THE SOURCE OF CONTINUED
OCCASIONAL SHOWER ACTIVITY. RELATIVE HUMIDITIES AT SAME LEVEL
FINALLY DROP TO NEAR 70 PERCENT BY 18Z MONDAY AND SHOWER COVERAGES
WILL DECREASE FROM THE EAST. THERE APPEARS TO BE ENOUGH MOISTURE IN
THE LOWER LAYERS OF THE ATMOSPHERE TO SUSTAIN SCATTERED SHOWERS ON
THE COASTS AND OVER THE SURROUNDING WATERS DURING THE NIGHT AND OVER
WESTERN INTERIOR SECTIONS DURING THE DAY WITH A MODEST INCREASE IN
ACTIVITY ONLY WHEN THE NEXT SEVERAL WAVES CROSS THROUGH THE AREA.

MODELS DO SPIN UP ANOTHER CIRCULATION EAST OF THE AREA LATER IN THE
WEEK...BUT LITTLE CONFIDENCE CAN BE PLACED IN THIS CENTER AT THIS
TIME...WAVE ACTIVITY IS MORE CERTAIN HOWEVER.

&&

.MARINE...WINDS ARE INCREASING NEAR THE CORE OF THE TROPICAL
DEPRESSION AND IT SHOULD BECOME A TROPICAL STROM WITHIN THE NEXT 6
TO 12 HOURS. SEAS WILL BE GENERATED AROUND THE SYSTEM AND WILL
REMAIN HIGH...5 TO 8 FEET...FOR ANOTHER 24 TO 36 HOURS. SOME WAVES
SHOULD MOVE ONTO THE WEST COAST OF PUERTO RICO UNTIL SUNDAY NIGHT.
ONCE IT MOVES OVER THE DOMINICAN REPUBLIC...SEAS HERE SHOULD
DIMINISH...AND ONLY LIMITED SWELL FROM THE STORM WILL ARRIVE ON OUR
NORTHERN SHORES AS IT TRAVELS NORTHWARD.

&&

.AVIATION...WINDS ALOFT REACHED A MAXIMUM SPEED OF 26 KNOTS OVER SAN
JUAN IN THE LATEST SOUNDING...BUT ARE STILL RUNNING FAIRLY STRONG.
THIS WILL MAKE FOR CONSIDERABLE LOW LEVEL WIND SHEAR NEAR
THUNDERSTORMS. THESE CONDITIONS WILL LAST FOR ANOTHER 24 TO 36
HOURS. AFTERWARD SHOWER AND THUNDERSTORM ACTIVITY WILL DECREASE AND
BE STRONGEST OVER INTERIOR PUERTO RICO DURING THE AFTERNOONS...AND
OVER THE ATLANTIC WATERS DURING THE NIGHT. PILOTS HEADING TOWARD
MIAMI AND THE DOMINICAN REPUBLIC SHOULD GET THE LATEST POSITION OF
TROPICAL DEPRESSION 25.

&&

.PRELIMINARY POINT TEMPS/POPS...
SJU  76  89  77  90 /  80  80  50  50
STT  76  85  77  86 /  80  70  50  50

&&

.SJU WATCHES/WARNINGS/ADVISORIES...
PR...FLASH FLOOD WATCH THROUGH LATE TONIGHT FOR PRZ002-PRZ003-PRZ004-
     PRZ006-PRZ007-PRZ009-PRZ010-PRZ011-PRZ012-PRZ013.

VI...NONE.

&&

SNELL

HAZARDOUS WEATHER OUTLOOK
NATIONAL WEATHER SERVICE SAN JUAN PR
630 AM AST SAT OCT 22 2005

PRZ001>013-AMZ710>750-231030-
630 AM AST SAT OCT 22 2005

THIS HAZARDOUS WEATHER OUTLOOK IS FOR PUERTO RICO.

.DAY ONE...TODAY AND TONIGHT

A STRONG TROPICAL WAVE AND ASSOCIATED SURFACE LOW...CENTERED NEAR
15.5 NORTH AND 67 WEST...WILL CONTINUE TO MOVE WEST NORTHWEST ACROSS
THE LOCAL AREA TODAY AND TONIGHT. VERY STRONG WINDS ACCOMPANYING
THIS TROPICAL WAVE...FROM 15 TO 25 MPH WITH HIGHER GUSTS...WILL
CONTINUE TO SWEEP THROUGH THE LOCAL ISLANDS TODAY AND WILL GENERATE
HIGH SEAS ACROSS THE LOCAL COASTAL WATERS. IN ADDITION...INTENSE
SQUALLS AND THUNDERSTORMS WILL ALSO MOVE NORTHWESTWARD THROUGH THE
AREA TODAY. THIS TROPICAL WAVE MAY INTENSIFY INTO A TROPICAL
DEPRESSION TODAY OR TONIGHT AS IT MOVES TOWARDS AND INTO HISPANIOLA.

A SMALL CRAFT ADVISORY IS IN EFFECT FOR ALL OF THE LOCAL ATLANTIC
AND CARIBBEAN WATERS.

FLASH FLOODING IS POSSIBLE TODAY ACROSS PORTIONS OF THE LOCAL
ISLANDS...ESPECIALLY DURING THE AFTERNOON HOURS.

.DAYS TWO THROUGH SEVEN...

LINGERING LOW LEVEL MOISTURE BEHIND THE EXITING TROPICAL WAVE WILL
PASS ACROSS THE LOCAL AREA SUNDAY WITH ASSOCIATED SHOWER AND
THUNDERSTORM ACTIVITY.

.SPOTTER CALL TO ACTION STATEMENT...

SPOTTER ACTIVATION MAY BE NECESSARY.

VIZ001-002-AMZ710>730-231030-
630 AM AST SAT OCT 22 2005

THIS HAZARDOUS WEATHER OUTLOOK IS FOR THE U.S. VIRGIN ISLANDS.

.DAY ONE...TODAY AND TONIGHT

A STRONG TROPICAL WAVE AND ASSOCIATED SURFACE LOW...CENTERED NEAR
15.5 NORTH AND 67 WEST...WILL CONTINUE TO MOVE WEST NORTHWEST ACROSS
THE LOCAL AREA TODAY AND TONIGHT. VERY STRONG WINDS ACCOMPANYING
THIS TROPICAL WAVE...FROM 15 TO 25 MPH WITH HIGHER GUSTS...WILL
CONTINUE TO SWEEP THROUGH THE LOCAL ISLANDS TODAY AND WILL GENERATE
HIGH SEAS ACROSS THE LOCAL COASTAL WATERS. IN ADDITION...INTENSE
SQUALLS AND THUNDERSTORMS WILL ALSO MOVE NORTHWESTWARD THROUGH THE
AREA TODAY. THIS TROPICAL WAVE MAY INTENSIFY INTO A TROPICAL
DEPRESSION TODAY OR TONIGHT AS IT MOVES TOWARDS AND INTO HISPANIOLA.

A SMALL CRAFT ADVISORY IS IN EFFECT FOR ALL OF THE LOCAL ATLANTIC
AND CARIBBEAN WATERS.

FLASH FLOODING IS POSSIBLE TODAY ACROSS PORTIONS OF THE LOCAL
ISLANDS...ESPECIALLY DURING THE AFTERNOON HOURS.

.DAYS TWO THROUGH SEVEN...

LINGERING LOW LEVEL MOISTURE BEHIND THE EXITING TROPICAL WAVE WILL
PASS ACROSS THE LOCAL AREA SUNDAY WITH ASSOCIATED SHOWER AND
THUNDERSTORM ACTIVITY.

.SPOTTER CALL TO ACTION STATEMENT...

SPOTTER ACTIVATION MAY BE NECESSARY.

STAY TUNED TO NOAA WEATHER RADIO AND OTHER LOCAL MEDIA FOR FURTHER
DETAILS OR UPDATES.

FOR ADDITIONAL INFORMATION...VISIT THE NATIONAL WEATHER SERVICE WEB
SITE FOR PUERTO RICO AND THE U.S. VIRGIN ISLANDS AT (ALL LOWERCASE
LETTERS): HTTP://WWW.SRH.NOAA.GOV/SJU.