Areal Flood Warning 28, NWS JSJ

AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE SAN JUAN PR
309 PM AST FRI JUL 1 2011

.SYNOPSIS...AT UPPER LEVELS...A CUT-OFF LOW OVER EASTERN CUBA WILL
RETREAT NORTHEAST AS HIGH PRESSURE RIDGES IN OVER THE LOCAL AREA
OVER THE HOLIDAY WEEKEND. THIS HIGH PRESSURE WILL MOVE TO CUBA
DURING THE WEEK. A TROUGH WILL DIG SOUTHWEST OVER THE LEEWARD
ISLANDS DURING THE FOLLOWING WEEKEND.

AT MID LEVELS...A WEAK LOBE OF HIGH PRESSURE WILL PERSIST OVER THE
LOCAL AREA RIDGING IN FROM THE NORTH. MID LEVELS ARE ONLY DRY
TUESDAY THROUGH FRIDAY.

AT LOWER LEVELS...A STRONG TROPICAL WAVE IS NOW LOCATED IN THE
ANEGADA PASSAGE WITH MOST OF ITS ASSOCIATED WEATHER AHEAD OF IT AS
FAR WEST AS THE MONA PASSAGE. IT IS EXPECTED TO MOVE WEST THROUGH
THE AREA SATURDAY MORNING WITH SOME TRAILING MOISTURE AND
CONVECTIVE ACTIVITY IN STRONG SOUTHEAST FLOW THROUGH MONDAY.
STRONG TRADE WINDS CONTINUE BUT CONDITIONS WILL BE DRIER TUESDAY
THROUGH THURSDAY.

&&

.DISCUSSION...GUSTY WINDS...SHOWERS AND THUNDERSTORMS MOVED INTO
SOUTHEAST PUERTO RICO AND THE CARIBBEAN WATERS TODAY...AND SHOWERS
AND THUNDERSTORMS FORMED OVER THE COASTAL PLAINS ON THE NORTH
COAST. IT IS EXPECTED THAT ACTIVITY WILL CONTINUE TO INCREASE OVER
THE AREA AND SPREAD NORTH INTO THE NORTHERN U.S. VIRGIN ISLANDS.
RAIN AMOUNTS OF 2 TO 4 INCHES ARE POSSIBLE SOUTHEAST PORTIONS AND
HIGHER ELEVATIONS OF PUERTO RICO AND SAINT CROIX. AT THIS TIME
WINDS AND SHOWERS ARE VERIFYING THE WETTER NAM MODEL AND IT IS
FORECASTING PULSES OF MOISTURE TO CONTINUE WITH THE WAVE AND IN
THE MOIST FLOW BEHIND IT ON AND OFF THROUGH MONDAY. MODELS ARE
DRIER AFTER THIS...BUT A SECOND TROPICAL WAVE WILL MOVE THROUGH
THE AREA ON FRIDAY.

A FLASH FLOOD WATCH FOR AT LEAST SAINT CROIX AND THE SOUTHEAST
HALF OF PUERTO RICO IS UNDER CONSIDERATION.

&&

.AVIATION...AREAS OF MVFR AND IFR WILL SPREAD OVER PUERTO RICO AND
THE U.S. VIRGIN ISLANDS TONIGHT IF THEY ARE NOT ALREADY UNDER.
CONTINUED POOR FLYING CONDITIONS WITH GUSTY SURFACE WINDS AND
STRONGER WINDS AT 3 TO 10 THOUSAND FEET WILL CONTINUE FOR THE NEXT
24 HOURS. LOCALLY HEAVY RAINS AND THUNDERSTORMS WILL ALSO PRESENT
HAZARDS TO AVIATION. TOPS OF MUCH OF THE CONVECTION IS 30 TO 40
THOUSAND FEET WITH ISOLATED TOPS TO 60 THOUSAND.

&&

.PRELIMINARY POINT TEMPS/POPS...
SJU  77  89  78  88 /  70  60  20  30
STT  79  88  80  90 /  80  60  20  20

&&

.SJU WATCHES/WARNINGS/ADVISORIES...
PR...SCA...TONGT...AMZ710-722-725-732-735-741.
VI...SCA...TONGT...AMZ710-722-725-732.
&&

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