Flash Flood Warning 20, NWS JSJ

515 
WGCA72 TJSJ 021517
FFSSJU

FLASH FLOOD STATEMENT
NATIONAL WEATHER SERVICE SAN JUAN PR
1117 AM AST SUN MAY 2 2010

PRC037-053-089-103-119-021524-
/O.EXP.TJSJ.FF.W.0020.000000T0000Z-100502T1515Z/
/00000.0.ER.000000T0000Z.000000T0000Z.000000T0000Z.OO/
LUQUILLO PR-NAGUABO PR-CEIBA PR-FAJARDO PR-RIO GRANDE PR-
1117 AM AST SUN MAY 2 2010

...THE FLASH FLOOD WARNING WILL EXPIRE AT 1115 AM AST FOR RIO
GRANDE...FAJARDO...CEIBA...NAGUABO AND LUQUILLO MUNICIPALITIES...

AT 1110 AM AST...THE HEAVY RAINFALL WHICH PLAGUED MUCH OF 
NORTHEASTERN PUERTO RICO EARLIER THIS MORNING WAS BEGINNING TO 
DIMINISH...AND THE RIO FAJARDO HAD SUBSIDED BELOW FLOOD STATE. FOR 
THESE REASONS...THE FLASH FLOOD WARNING FOR THIS AREA IS BEING 
ALLOWED TO EXPIRE. WHILE THE FLASH FLOOD WARNING IS BEING ALLOWED TO 
EXPIRE...AN URBAN AND SMALL STREAM FLOOD ADVISORY REMAINS IN EFFECT 
FOR THIS SAME AREA UNTIL 1215 PM AST THIS AFTERNOON.

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 1834 6563 1822 6560 1817 6574 1822 6581
      1828 6581 1832 6577

$$

SR

ADDITIONAL INFORMATION CAN BE FOUND AT /USE LOWER CASE LETTERS/:
     HTTP://WWW.WEATHER.GOV/SANJUAN

AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE SAN JUAN PR
529 AM AST SUN MAY 2 2010

.SYNOPSIS...AT UPPER LEVELS...A CUT-OFF LOW WILL FORM IN A DIGGING
TROUGH...EXTENDING SOUTHWEST THROUGH THE MONA PASSAGE INTO THE
CARIBBEAN...AND MOVE RAPIDLY SOUTHWEST MONDAY AND THEN WEST ON
TUESDAY BEFORE CROSSING CUBA AND BEING ABSORBED INTO ANOTHER
TROUGH ON THURSDAY. HIGH PRESSURE WILL BUILD OVER THE EASTERN
CARIBBEAN ON TUESDAY AND EXTEND NORTH OVER PUERTO RICO ON
WEDNESDAY. IT WILL MOVE OVER THE U.S. VIRGIN ISLANDS ON THURSDAY
NIGHT AND INTO THE TROPICAL ATLANTIC ON SATURDAY. ON SATURDAY A
TROUGH AT FLORIDA'S LATITUDE WILL PASS NORTH OF THE AREA WITH
ANOTHER SHORT WAVE CROSSING THE LOCAL ISLANDS ON MONDAY.

AT MID LEVELS...HIGH PRESSURE OVER CUBA WILL GIVE WAY TO THE WEAK CUT-
OFF LOW THAT MOVES INTO THE CARIBBEAN FROM THE NORTHEAST ON MONDAY
AND WILL RIDGE OVER FLORIDA TUESDAY. THE RIDGE WILL CONTINUE EAST
ON TUESDAY AND WEDNESDAY WHILE A LOW FORMS IN THE TROPICAL
ATLANTIC EAST OF THE WINDWARD ISLANDS. THE LOW WILL MOVE SLOWLY TO
THE NORTHEAST DURING THE REST OF THE WEEK WHILE HIGH PRESSURE
WRAPS AROUND IT. SOUTHWEST FLOW OVER THE LOCAL AREA WILL COMMENCE
LATE IN THE WEEK AS A TROUGH DIGS INTO THE NORTHWESTERN CARIBBEAN.

AT LOWER LEVELS...HIGH PRESSURE WILL REMAIN IN PLACE NORTH OF
PUERTO RICO THROUGH WEDNESDAY NIGHT NEAR 28 NORTH LATITUDE. A
FRONTAL BOUNDARY WILL ALSO SAG SOUTH TODAY...REFORM ON MONDAY
TO THE NORTH AND PASS THROUGH THE AREA AGAIN ON TUESDAY BEFORE DRY
AIR IS USHERED IN ON THURSDAY. A TROUGH WILL MOVE INTO THE AREA
FROM THE EAST AND BRING MOISTURE BACK TO THE AREA ON FRIDAY AND
SATURDAY OF THE UPCOMING WEEK. ALTHOUGH THE HIGH PRESSURE BREAKS
OUT OF ITS LOCK ON THURSDAY AND BUILDS INTO THE CENTRAL ATLANTIC
BY SATURDAY...THE LOCAL AREA NEVER BREAKS FREE OF THE RIDGE THAT
EXTENDS WEST AND CROSSES FLORIDA WHICH MAINTAINS THE EASTERLY
TRADE WIND FLOW OVER PUERTO RICO AND THE U.S. VIRGIN ISLANDS.

&&

.DISCUSSION...CONSIDERABLE SHOWER ACTIVITY DEVELOPED JUST NORTH OF
PUERTO RICO...CULEBRA...SAINT THOMAS AND SAINT JOHN AND SETTLED
SOUTH OVER THE ISLANDS EARLY THIS MORNING. AS MUCH AS 1.5 TO 2
INCHES MAY HAVE FALLEN IN ONE AREA OF CAROLINA BUT MOST AREAS ON
THE NORTH COAST OF PUERTO RICO AND AREAS DIRECTLY EAST RECEIVED A
MEASURABLE AMOUNT OF LESS THAN ONE INCH. WATER VAPOR IMAGERY
SHOWS THE UPPER LEVEL TROUGH FORMING OVER THE EASTERN DOMINICAN
REPUBLIC AND IT IS EXPECTED THAT THE UPPER LEVEL CUT-OFF LOW WILL
SOON APPEAR. THE FRONTAL BOUNDARY IS SLOWING ITS SOUTHWARD SINK
AND IT IS LIKELY THAT IT WILL STILL BE ENCOUNTERED OVER CENTRAL
PUERTO RICO BY 18Z. THIS SHOULD BE IDEAL FOR THE DEVELOPMENT OF
SHOWERS AND SCATTERED THUNDERSTORMS IN THAT AREA AND IT IS LIKELY
THAT SOME AREAS OF WESTERN AND INTERIOR PUERTO RICO WILL HAVE
SOME URBAN AND SMALL STREAM FLOODING...AND PERHAPS SOME RIVER
RISES IF ENOUGH HEATING DEVELOPS. HAVE HELD OFF ON ISSUING A
FLASH FLOOD WATCH FOR THE AREA DUE TO LACK OF UPPER LEVEL
DYNAMICS AFTER 02/12Z AND UNCERTAINTY OF MID LEVEL MOISTURE. IT
MAY STILL BE NECESSARY SHOULD THE 12Z SOUNDING SHOW FAVORABLE
CONDITIONS. THE BOUNDARY MOVES SOUTH AND FADES TONIGHT. THE GFS
AND NAM BRING MOISTURE BANDS FROM THE EAST OVER THE AREA ON
MONDAY...WHILE THE ECMWF HOLD A GENERALLY MOIST ATMOSPHERE OVER
THE AREA UNTIL DRYER AIR FORCES IT OUT AND AWAY TO THE SOUTHWEST
TUESDAY NIGHT AND WEDNESDAY. THE ECMWF ALSO BRINGS THE SAME
BOUNDARY BACK ON FRIDAY WHILE THE GFS BRINGS IN WAVES OF MOISTURE
THAT CONTINUE FROM FRIDAY TO THE FOLLOWING TUESDAY...LIKELY RIGHT
ON THROUGH MID- MONTH. MEANWHILE FAVORABLE MJO CONDITIONS SHOW NO
SIGN OF LEAVING THE AREA SOON. IN ANY CASE EXPECT WET CONDITIONS
ACROSS THE AREA UNTIL TUESDAY NIGHT OR WEDNESDAY AS THE SECOND
CLIMATOLOGICALLY WETTEST MONTH IN SAN JUAN AND MUCH OF THE AREA
MAKES ITS ENTRANCE.

&&

.AVIATION...
SHRA OR VCSH CONDITIONS WILL PREVAIL ACROSS TJSJ...TJBQ...TIST
THROUGH 02/18Z WITH TEMPORARY PERIODS OF MVFR. TJMZ WILL REMAIN
VFR THROUGH 02/16Z...SHOWERS AND ISOLATED THUNDERSTORMS WILL
DEVELOP AROUND 02/17-02/21. TJPS AND TISX VFR THROUGH 02/17Z WITH
VCNTY SHWRS REST OF PERIOD. LLVL WIND FLOW ENE AT 15 TO 20 KTS
WITH GUSTS.

&&

.MARINE...SEAS ARE EXPECTED TO INCREASE SOMEWHAT WITH WINDS BUT
SHOULD IN GENERAL REMAIN JUST BELOW SMALL CRAFT ADVISORY
CONDITIONS. SEAS IN THE ATLANTIC DIMINISH TUESDAY THROUGH
SATURDAY...BUT INCREASE A LITTLE IN THE CARIBBEAN LATE IN THE WEEK.

&&

.PRELIMINARY POINT TEMPS/POPS...
SJU  87  76  88  76 /  60  40  50  70
STT  86  78  87  78 /  60  40  50  60

&&

.SJU WATCHES/WARNINGS/ADVISORIES...
PR...NONE.
VI...NONE.
&&

07/12

HAZARDOUS WEATHER OUTLOOK FOR PUERTO RICO AND THE U.S. VIRGIN
ISLANDS
NATIONAL WEATHER SERVICE SAN JUAN PR
634 AM AST SUN MAY 2 2010

AMZ710>745-PRZ001>013-031045-
SAN JUAN AND VICINITY-NORTHEAST-SOUTHEAST-EASTERN INTERIOR-
NORTH CENTRAL-CENTRAL INTERIOR-PONCE AND VICINITY-NORTHWEST-
WESTERN INTERIOR-MAYAGUEZ AND VICINITY-SOUTHWEST-CULEBRA-VIEQUES-
THE NEARSHORE AND OFF SHORE ATLANTIC AND CARIBBEAN COASTAL WATERS-
634 AM AST SUN MAY 2 2010

THIS HAZARDOUS WEATHER OUTLOOK IS FOR PUERTO RICO AND THE
ADJACENT COASTAL WATERS.

.DAY ONE...TODAY AND TONIGHT

NUMEROUS SHOWERS AND ISOLATED THUNDERSTORMS WILL BE THE RULE
ACROSS THE NORTHERN THIRD OF MAINLAND PUERTO RICO THIS MORNING
WITH ISOLATED SHOWERS EXPECTED ACROSS THE WEST AND SOUTHERN
PORTIONS OF THE ISLAND. SHOWERS WILL BECOME SCATTERED ACROSS THE
NORTHERN THIRD OF MAINLAND PUERTO RICO LATER THIS MORNING.
HOWEVER...SHOWERS AND THUNDERSTORMS ARE EXPECTED TO BECOME MORE
NUMEROUS THIS AFTERNOON ACROSS THE INTERIOR...WEST AND SOUTHWEST
SECTIONS OF PUERTO RICO. HEAVY SHOWERS WILL RESULT IN AREAS OF AT
LEAST SOME URBAN AND SMALL STREAM FLOODING.

.DAYS TWO THROUGH SEVEN...MONDAY THROUGH SATURDAY

SHOWERS AND THUNDERSTORMS ARE EXPECTED TO DEVELOP DURING THE
AFTERNOONS ACROSS DIURNALLY FAVORED SECTIONS OF PUERTO RICO.
THESE SHOWERS WILL BE CAPABLE OF PRODUCING AREAS OF LOCALLY HEAVY
RAIN.

.SPOTTER INFORMATION STATEMENT...

SPOTTER ACTIVATION MAY BE REQUIRED.

AMZ715-725-VIZ001-002-031045-
ST. THOMAS ST. JOHN ADJACENT ISLANDS-ST CROIX-
NEARSHORE ATLANTIC AND ADJACENT CARIBBEAN COASTAL WATERS-
634 AM AST SUN MAY 2 2010

THIS HAZARDOUS WEATHER OUTLOOK IS FOR THE U.S. VIRGIN ISLANDS AND
THE ADJACENT COASTAL WATERS.

.DAY ONE...TODAY AND TONIGHT

NUMEROUS SHOWERS AND ISOLATED THUNDERSTORMS WILL CONTINUE THROUGH
MOST OF THIS MORNING WITH PERIODS OF HEAVY RAINFALL POSSIBLE.
FLOODING OF LOW LYING AND POOR DRAINAGE AREAS ARE LIKELY.

.DAYS TWO THROUGH SEVEN...MONDAY THROUGH SATURDAY

NO HAZARDOUS WEATHER IS EXPECTED AT THIS TIME.

.SPOTTER INFORMATION STATEMENT...

SPOTTER ACTIVATION WILL NOT BE NEEDED.