Area Forecast Discussion
Issued by NWS San Juan, PR

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FXCA62 TJSJ 030229
AFDSJU

AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE SAN JUAN PR
1029 PM AST MON MAR 2 2015

.UPDATE...SCATTERED SHOWERS AFFECTED PORTIONS OF PR...ESPECIALLY
SW-PR IN THE AFTERNOON HOURS. THE ACCUMULATIONS WERE NOT ENOUGH TO
CAUSE ANY FLOODING BUT THERE WERE STILL SOME MODERATE
SHOWERS...HOWEVER NO THUNDERSTORMS WERE OBSERVED. LATER IN THE
EVENING BRIEF SCATTERED TO LOCALLY NUMEROUS SHOWERS STARTED MOVING
INTO THE LOCAL AREA. THE ACCUMULATIONS WITH THESE SHOWERS HAVE NOT
BEEN SIGNIFICANT SO FAR AS THEY ARE MOVING QUICKLY. SOME CHANGES
WERE MADE TO THE SHORT TERM FORECAST AS THE AERIAL COVERAGE OF THE
SHOWERS WAS LARGER THAN THE FORECAST CALLED FOR...THEREFORE THE
POPS WERE INCREASED SLIGHTLY. OTHER THAN THAT NOTHING HAS CHANGED
FROM THE PREVIOUS DISCUSSION.


&&

.AVIATION...VFR. BRIEF PASSING VCSH/SHRA ALL TAF SITES XCP BTWN
03/06Z-03/17Z TJMZ AND TJPS. SHRA RESUMING OVER WRN PR AFT 03/17Z
WITH AREAS OF MTN OBSCURATIONS. WINDS ALF NE-ENE 15 TO 20 KT BLO
FL200...LIGHTER NR SFC TILL 03/14Z.

&&

.MARINE...SMALL CRAFT ADVISORY CONTINUES IN EFFECT FOR MOST OF THE
LOCAL WATERS. LATEST GUIDANCE SUGGESTS SEAS OF 7 TO 8 FEET ACROSS
MOST OF THE SURROUNDING WATERS THROUGH THIS WEEK. COMPARISON
BETWEEN THE MODEL GUIDANCE AND THE OBSERVED WAVE HEIGHTS ARE VERY
CLOSE...SO THE MODELS SEEM TO BE INITIALIZING WELL. FOR THAT
REASON THE SMALL CRAFT ADVISORY WAS KEPT UNTIL LATE THURSDAY NIGHT.


&&

.PREV DISCUSSION... /ISSUED 443 PM AST MON MAR 2 2015/

SYNOPSIS...
A TROUGH ALOFT WILL CONTINUE TO BUILD OVER THE EASTERN CARIBBEAN
TODAY INTO TUESDAY. ITS AXIS WILL MOVE OVER THE LESSER ANTILLES BY
WEDNESDAY. THE LOCAL ISLANDS WILL BE IN THE SUBSIDENCE AREA
BETWEEN AN UPPER LEVEL RIDGE TO THE WEST AND AN UPPER LEVEL TROUGH
TO THE EAST OF THE ISLANDS. AT THE SURFACE...PATCHES OF SHALLOW
MOISTURE WILL CONTINUE TO MOVE ACROSS THE LOCAL AREA FROM TIME TO
TIME DURING THE REST OF THE WORK WEEK.

DISCUSSION...

UNDER AN AMPLIFYING TROUGH ALOFT WITH BREEZY CONDITIONS...TRADE
WIND SHOWERS WILL CONTINUE TO PREVAIL ACROSS THE FORECAST AREA
TODAY AND TUESDAY WITH EVEN SOME THUNDERSTORMS DEVELOPING OVER SW
PR IN THE AFTERNOON HOURS. MODEL GUIDANCE CONTINUE TO SUGGEST
BREEZY/WINDY CONDITIONS FOR THE REST OF THE WEEK...AS A MIGRATORY
SURFACE HIGH PRESSURE MOVES OVER WESTERN ATLANTIC OCEAN DRIFTING
TOWARD THE CENTRAL ATLANTIC BY MID WEEK. AS A RESULT....FRESH TO
LOCALLY STRONG TRADE WINDS ARE EXPECTED AT LEAST UNTIL FRIDAY.

AN UPPER LEVEL RIDGE WILL BUILD ALOFT BY MID WEEK AND THE
AVAILABLE MOISTURE IS EXPECTED TO DECREASE. THEREFORE...LATE
THIS WEEK DRIER AND STABLE CONDITIONS ARE EXPECTED WITH AN OVERALL
FAIR WEATHER PATTERN. KEEP IN MIND THAT OCCASIONAL TRADE WIND
SHOWERS CAN NOT BE RULE OUT ACROSS THE REGION.

AVIATION...BRIEF MVFR CONDS WILL REMAIN POSSIBLE IN AND AROUND
TJMZ/TJPS TIL 22Z IN SHRA AND AN ISOLATED TSRA IS POSSIBLE. AFT
02/22Z MOSTLY VFR CONDS WITH BRIEF PASSING SHOWERS AT LEEWARD AND
USVI TERMINALS AS WELL AS TJSJ. EAST NORTHEAST WINDS 15 TO 20 KNOTS
BECOMING 5 TO 10 OVERNIGHT

MARINE...FRESH TRADE WINDS WILL CONTINUE TO GENERATE WIND WAVES
NEAR 7 FEET OVER THE NEXT FEW DAYS...THEREFORE SMALL CRAFT
ADVISORIES WILL REMAIN IN EFFECT FOR MOST OF THE REGIONAL
WATERS...EXCEPT FOR THE NEAR SHORE WATERS OF WESTERN AND SOUTHERN
PUERTO RICO...WHERE SMALL CRAFT OPERATORS SHOULD EXERCISE CAUTION.
ALTHOUGH THE WINDS WILL CONTINUE TO DIMINISH THIS AFTERNOON ACROSS
THE COASTAL WATERS...STILL EXPECT THE MODERATE TO LOCALLY STRONG
EAST NORTHEAST TRADE WINDS TO GENERATE ROUGH AND HAZARDOUS WIND
DRIVEN SEA CONDITIONS. PLEASE REFER TO THE LATEST COASTAL WATERS
FORECAST AND MARINE WEATHER MESSAGE ISSUED BY THE NATIONAL WEATHER
SERVICE WFO SAN JUAN PR.

&&

.PRELIMINARY POINT TEMPS/POPS...
SJU  74  84  75  86 /  60  40  40  40
STT  73  85  73  86 /  40  40  40  40

&&

.SJU WATCHES/WARNINGS/ADVISORIES...
PR...NONE.
VI...NONE.
COASTAL WATERS...SMALL CRAFT ADVISORY UNTIL 6 AM AST FRIDAY FOR ANEGADA PASSAGE
     SOUTHWARD TO 17N-ATLC WATERS OF PUERTO RICO AND USVI FROM
     10NM TO 19.5N-CARIBBEAN WATERS OF PUERTO RICO FROM 10 NM TO
     17N-COASTAL WATERS OF NORTHERN PUERTO RICO OUT 10 NM-
     COASTAL WATERS OF NORTHERN USVI AND CULEBRA OUT 10 NM-
     COASTAL WATERS OF SOUTHERN USVI VIEQUES AND EASTERN PUERTO
     RICO OUT 10 NM-MONA PASSAGE SOUTHWARD TO 17N.

&&

$$

12/25








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