Heavy Rain in Puerto Rico, May 12, 2004

PUERTO RICO AND U.S. VIRGIN ISLANDS FORECAST DISCUSSION
NATIONAL WEATHER SERVICE SAN JUAN PR
337 PM AST WED MAY 12 2004

.SYNOPSIS...MID TO UPPER LEVEL LONG WAVE TROUGH NOW EXTENDS FROM THE
WEST CENTRAL ATLANTIC SOUTHWEST ACROSS THE LOCAL REGION. WEAK MID
LEVEL SHORT WAVE VORTICIES CONTINUE TO MOVE EASTWARD THROUGH THE
BASE OF THE TROUGH WHICH LAYS ACROSS THE DOMINICAN REPUBLIC AND
LOCAL ISLANDS. THE REMNANTS OF COLD FRONT EXTENDS SOUTH FROM THE
NORTH CENTRAL ATLANTIC TO NEAR 30 NORTH 42 DEGREES WEST WITH INDUCED
TROUGHING AND ASSOCIATED FRONTAL BOUNDARY EXTENDING FURTHER
SOUTHWEST INTO THE TROPICAL ATLANTIC. BROAD SURFACE HIGH PRESSURE
SYSTEM LAYS ACROSS THE WEST AND CENTRAL ATLANTIC PRODUCING A STRONG
PRESSURE GRADIENT AND MODERATE TO FRESH EASTERLY TRADE WIND FLOW
ACROSS THE LOCAL REGION.

&&

.DISCUSSION...LATEST 12Z SOUNDING FOR TJSJ CONTINUES TO REFLECT A
MOIST AND UNSTABLE ATMOSPHERE ACROSS THE LOCAL AREA. EXPECT
CONSIDERABLE AMOUNTS OF LEVEL MOISTURE ADVECTION ACROSS THE LOCAL
REGION TODAY AND THROUGH THE REST OF THE WEEK. SHOWER ACTIVITY AND
ISOLATED THUNDERSTORMS WILL CONTINUE TO DEVELOP AND MOVE WEST
ACROSS PUERTO RICO...AND ALSO THE U.S. VIRGIN ISLANDS TODAY
ESPECIALLY IN AND AROUND THE ISLAND OF SAINT CROIX. GIVEN THE
SATURATED TERRAIN CONDITIONS OVER THE NORTH SECTIONS OF PUERTO
RICO...AND THE HIGH RIVER LEVELS ACROSS THESE AREAS...URBAN...STREAM
AND RIVER FLOODING CONDITIONS ARE MORE THAN LIKELY TO OCCUR ON A
DAILY BASIS THROUGH THE REST OF THE WEEK. A FLASH FLOOD WATCH HAS
BEEN ISSUED FOR THE NORTHERN THIRD OF PUERTO RICO UNTIL 8 PM AND
FLASH FLOOD WARNINGS ARE NOW IN EFFECT FOR PORTION OF THE NORTHEAST
THIRD OF PUERTO RICO UNTIL 530 PM. ALSO THERE IS HIGH POTENTIAL
MUDSLIDES DUE TO THE PRESENT AND PAST RAINS THAT HAVE OCCURRED
ACROSS THESE AREAS.

&&

.MARINE....DUE TO THE ROUGH AND CHOPPY SEA CONDITIONS PRODUCED BY
THE MODERATE TO FRESH EASTERLIES...SMALL CRAFT SHOULD EXERCISE
CAUTION ACROSS THE ATLANTIC AND CARIBBEAN WATERS...EXCEPT FOR THE
NEAR SHORE WATERS OF WESTERN PUERTO RICO.

&&

.PRELIMINARY POINT TEMPS/POPS...
SJU  73  84  73  86 /  40  50  60  40
STT  73  83  73  85 /  40  40  60  40

&&

.SJU WATCHES/WARNINGS/ADVISORIES...
PR...FFA PRZ001-002-004>006-009
VI...NONE.

&&

MITCHELL

HAZARDOUS WEATHER OUTLOOK
NATIONAL WEATHER SERVICE SAN JUAN PR
610 AM AST WED MAY 12 2004

PRZ001>013-AMZ710>750-131000-
610 AM AST WED MAY 12 2004

THIS HAZARDOUS WEATHER OUTLOOK IS FOR PUERTO RICO.

.TODAY...MODERATE TO STRONG EAST WINDS IN THE LOW LEVELS WILL
COMBINE WITH THE MOISTURE REMAINING FROM THE WEAK FRONTAL TROUGH
THAT LIES TO THE EAST AND SOUTH OF THE AREA TO PRODUCE SCATTERED TO
NUMEROUS SHOWERS. MOST SIGNIFICANT PROBLEM WILL BE RAINFALL
ACCUMULATIONS THIS AFTERNOON SINCE GROUND CONDITIONS ARE SATURATED
FROM PREVIOUS DAYS RAINFALL AND ANY LOCALLY HEAVY RAINS WILL CAUSE
SMALL STREAM AND RIVER LEVELS TO OVERFLOW THEIR BANKS MAINLY ALONG
THE NORTH CENTRAL FROM THE MAIN RIVERS AND NORTHEAST AND SAN JUAN
AND VICINITY FOR THE SMALL STREAMS. A SLIGHT CHANGE IN THE LOW LEVEL
WINDS TO A MORE EASTERLY DIRECTION WILL ALLOW FOR THE STRONG
WESTERLY WINDS AT THE UPPER LEVELS COMBINED WITH LOCAL EFFECTS TO
ALLOW FOR SHOWERS AND THUNDERSTORMS TO DEVELOP THIS AFTERNOON OVER
THE WEST INTERIOR.

MARINE CONDITIONS WILL CONTINUE ROUGH AND CHOPPY ALONG OFF SHORE
ATLANTIC WATERS. ELSEWHERE SMALL CRAFT SHOULD EXERCISE CAUTION
ELSEWHERE EXCEPT THE WEST WATERS.

.SPOTTER CALL TO ACTION STATEMENT...
SPOTTER ACTIVATION MAY BE REQUIRED.

.DAYS TWO THROUGH SEVEN...

SERIES OF UPPER LEVEL DISTURBANCES WILL TRAVEL AROUND THE BASE OF AN
UPPER LEVEL TROUGH THAT WILL SETTLE JUST WEST OF PUERTO RICO ON
THURSDAY TO PROVIDE UNSTABLE CONDITIONS THROUGH FRIDAY. THIS UPPER
TROUGH WILL INTERACT WITH THE MOISTURE LEFT OVER BY THE WEAK FRONTAL
BOUNDARY TO PRODUCE SCATTERED TO NUMEROUS SHOWERS AT NIGHT AND
DURING THE MORNING OVER THE NEXT FIVE DAYS AND ISOLATED
THUNDERSTORMS MAINLY DURING THE AFTERNOON HOURS. LOCALIZED FLASH
FLOODING AND SMALL STREAM FLOODING IS LIKELY TO CONTINUE.

A MODERATE TO FRESH WIND FLOW AND CHOPPY SEAS WILL PREVAIL ACROSS
THE LOCAL WATERS THROUGH NEXT WEEK.

VIZ001-002-AMZ710>730-131000-
610 AM AST WED MAY 12 2004

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

.TODAY...SCATTERED TO NUMEROUS SHOWERS WILL CONTINUE MOVE WEST
ACROSS THE U.S. VIRGIN ISLANDS AND THE TERRITORIAL WATERS THROUGH
THE NEXT 24 HOURS. SHOWERS WILL BE MORE NUMEROUS WITH ISOLATED
THUNDERSTORMS JUST NEAR AND SOUTHWEST OF ST CROIX. LIGHT TO MODERATE
RAINFALL ACCUMULATIONS ARE TO BE EXPECTED. URBAN AND GUT FLOODING
POSSIBLE IN ST CROIX.

.SPOTTER CALL TO ACTION STATEMENT...
SPOTTER ACTIVATION IS NOT ANTICIPATED.

.DAYS TWO THROUGH SEVEN...

SCATTERED SHOWERS WILL CONTINUE ACROSS THE U.S. VIRGIN ISLANDS
BECOMING NUMEROUS AT TIMES DUE TO MOIST EASTERLY WIND FLOW THAT
SHOULD PERSIST INTO NEXT WEEK.

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.

RM