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000
FXCA62 TJSJ 050848
AFDSJU

AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE SAN JUAN PR
448 AM AST THU MAR 5 2015

.SYNOPSIS...UPPER LEVEL TROUGH EXTENDING FROM THE CENTRAL ATLANTIC
ACROSS THE NORTHERN LEEWARDS ISLANDS...EAST OF PUERTO RICO...AND
THEN ACROSS THE CENTRAL CARIBBEAN...IS EXPECTED TO REMAIN CLOSE TO
THE REGION UNTIL AT LEAST SATURDAY. UPPER LEVEL RIDGE WILL REMAIN TO
THE WEST OF THE TROUGH AND IT IS EXPECTED TO HOLD OVER THE REGION
FOR THE NEXT FEW DAYS. SURFACE HIGH PRESSURE WELL NORTHEAST OF THE
REGION WILL MAINTAIN A MODERATE TO STRONG LOW LEVEL WIND FLOW ACROSS
THE NORTHEAST CARIBBEAN FOR THE NEXT SEVERAL DAYS.

&&

.DISCUSSION...DOPPLER WEATHER RADAR DETECTED ONLY ISOLATED SHOWERS
OVER THE COASTAL WATERS. HOWEVER...NOT SIGNIFICANT PRECIPITATION WAS
DETECTED OVER ANY OF LOCAL ISLANDS OVERNIGHT AND SO FAR THIS
MORNING. STRONG SURFACE TO MID LEVEL RIDGE WILL REMAIN AS THE MAIN
WEATHER FEATURES ACROSS THE NORTHEAST CARIBBEAN FOR THE NEXT SEVERAL
DAYS. THE SURFACE HIGH PRESSURE IS EXPECTED TO MAINTAIN A TIGHT
PRESSURE GRADIENT ACROSS THE REGION. THIS WILL LEAD TO FAIRLY STRONG
EASTERLY TRADE WINDS AND MOSTLY FAIR WEATHER CONDITIONS ACROSS THE
LOCAL ISLANDS. HOWEVER...VERY SMALL PATCHES OF LOW LEVEL MOISTURE
EMBEDDED IN THE TRADES WILL INDUCE THE DEVELOPMENT OF BRIEF PASSING
SHOWERS ACROSS EASTERN AND NORTHERN SECTIONS OF PUERTO RICO...
VIEQUES...CULEBRA AND ACROSS THE U.S. VIRGIN ISLANDS DURING THE
NIGHTS AND EARLY MORNING HOURS...WITH LIMITED CONVECTION OVER
WESTERN AND INTERIOR PUERTO RICO DURING THE AFTERNOONS. GFS MODEL
GUIDANCE SUGGESTS THAT THIS DRIER AND STABLE WEATHER CONDITIONS
WILL CONTINUE OVER THE REGION TODAY AND INTO THE UPCOMING WEEKEND.
THIS DRY WEATHER PATTERN IN COMBINATION WITH STRONG TRADES ACROSS
THE REGION WILL INCREASE THE FIRE HAZARDS ESPECIALLY OVER THE
SOUTHERN SLOPES OF PUERTO RICO. STAY TUNED.

&&

.AVIATION...MOSTLY VFR CONDITIONS WILL PREVAIL THROUGH THE
FORECAST PERIOD ACROSS THE LOCAL FLYING AREA. VCSH EXPECTED ACROSS
PARTS OF THE LOCAL TERMINALS...WITH WEATHER DRYING UP IN THE
MORNING HOURS. SFC WINDS WILL BE MAINLY FROM THE EAST TO E-NE...
INCREASING TO AROUND 20KTS AFTER 05/14Z AND GUSTY.

&&

.MARINE...BREEZY TO WINDY CONDITIONS WILL KEEP THE CHOPPY TO ROUGH
CONDITIONS ACROSS THE LOCAL WATERS OVER THE NEXT SEVERAL DAYS.
MARINERS SHOULD EXPECTED SEAS OF 6-8 FEET AND WINDS OF 15-23 KT WITH
OCCASIONAL WIND GUSTS OF 25-30 KT.

&&

.FIRE WEATHER...STRONG MID TO UPPER LEVEL HIGH PRESSURE RIDGE
BUILDING ACROSS THE REGION WILL SUPPORT UPPER LEVEL CONVERGENCE
AND RAPID DRYING OF FUELS TODAY ESPECIALLY ACROSS THE SOUTH
COASTAL PLAINS. MINIMUM RELATIVE HUMIDITY VALUES ARE EXPECTED TO
FALL SIGNIFICANTLY AND REACH NEAR CRITICAL LEVELS IN SOME
AREAS. THE INCREASING EAST NORTHEAST TRADE WINDS WILL LEAD TO
BREEZY CONDITIONS. THESE FEATURES WILL INDUCE AN ELEVATED FIRE
WEATHER CONDITIONS FOR PORTIONS OF THE SOUTH COASTAL PLAINS...AND
MONA ISLAND THIS MORNING AND INTO THE AFTERNOON HOURS.

&&

.PRELIMINARY POINT TEMPS/POPS...
SJU  86  74  87  74 /  20  10  10  20
STT  85  74  86  75 /  20  20  20  20

&&

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

     SMALL CRAFT ADVISORY UNTIL 6 PM AST THIS EVENING FOR COASTAL
     WATERS OF SOUTHERN PUERTO RICO OUT 10 NM.

     SMALL CRAFT ADVISORY FROM NOON FRIDAY TO 6 AM AST SATURDAY FOR
     COASTAL WATERS OF NORTHWESTERN PUERTO RICO OUT 10 NM-
     COASTAL WATERS OF SOUTHERN PUERTO RICO OUT 10 NM.

     SMALL CRAFT ADVISORY UNTIL NOON AST SATURDAY FOR COASTAL WATERS
     OF NORTHERN PUERTO RICO OUT 10 NM.

&&

$$

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