Area Forecast Discussion
Issued by NWS San Juan, PR

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FXCA62 TJSJ 230909 CCA
AFDSJU

AREA FORECAST DISCUSSION...CORRECTED
NATIONAL WEATHER SERVICE SAN JUAN PR
506 AM AST WED APR 23 2014

.SYNOPSIS...A ZONAL FLOW WILL CONTINUE TO PREVAIL ACROSS THE
LOCAL AREA AS AN UPPER LEVEL TROUGH DOMINATES THE ATLANTIC.
SURFACE HIGH PRESSURE WILL BUILD NORTH OF THE AREA OVER THE
WEEKEND.

&&

.DISCUSSION...PARTLY CLOUDY SKIES PREVAILED ACROSS THE LOCAL ISLANDS
OVERNIGHT...WITH SHOWERS OBSERVED ACROSS SOUTHEAST PUERTO RICO...SAINT
THOMAS AND SAINT JOHN. TEMPERATURES WERE IN THE LOWER 80S AT LOWER
ELEVATIONS WITH LIGHT AND VARIABLE WINDS.

A GENERALLY FAIR AND MAINLY STABLE WEATHER PATTERN WILL CONTINUE TO
PREVAIL ACROSS PUERTO RICO AND THE US VIRGIN ISLANDS DURING THE NEXT
TWO DAYS OR SO...AS A ZONAL FLOW CONTINUES TO DOMINATE THE NORTHEASTERN
CARIBBEAN...CREATING AND MAINTAINING OVERALL SUBSIDENCE AND MOSTLY
DRY CONDITIONS ALOFT. HOWEVER...DUE TO A WEAK SOUTHERLY LOW LEVEL
WIND FLOW...BETTER LOCAL SEA BREEZE VARIATIONS ARE ANTICIPATED...
RESULTING IN SOME DIURNALLY INDUCED SHOWERS AND POSSIBLY A LATE
AFTERNOON THUNDERSTORM MAINLY ACROSS PARTS OF THE NORTH AND
CENTRAL SECTIONS OF PUERTO RICO EACH DAY. AS THE AFOREMENTIONED
SOUTHERLY FLOW PREVAILS...WARMER THAN NORMAL TEMPERATURES WILL
CONTINUE.

GFS AND WRF CONTINUE TO SUGGEST A SLIGHT INCREASE IN MOISTURE FRIDAY
AND INTO EARLY NEXT WEEK. THIS MOISTURE ADVECTION IS ASSOCIATED
WITH INCREASING EAST SOUTHEAST TRADE WINDS AND A SERIES OF TROUGHS
MOVING NORTH OF THE AREA. THIS ALONG WITH LOCAL AND DIURNAL EFFECTS
WILL ALLOW FOR BETTER CHANCES OF AFTERNOON CONVECTION INLAND FRIDAY
THROUGH EARLY NEXT WEEK. OVERALL HOWEVER....LOOK FOR MOSTLY FAIR
WEATHER SKIES TO PREVAIL WITH PLENTY OF SUNSHINE ACROSS THE
ISLANDS.

&&

.AVIATION...VFR CONDITIONS ARE EXPECTED ACROSS THE LOCAL TERMINALS
FOR THE NEXT 24 HOURS. LIGHT WINDS...MAINLY FROM THE SOUTHEAST
EXPECTED FOR THE REST OF THE NIGHT...BECOMING ESE AFTER 23/13Z AT
AROUND 10 KT WITH SEA BREEZE VARIATIONS.

&&

.MARINE...WINDS 10-15 KT AND SEAS 2-4 FT THRU FRI. WINDS STRENGTHEN
SOME DURING THE WEEKEND WITH SEAS BECOMING 4-6 FT IN EAST GENERATED
WIND WAVES AND MODERATE NORTH SWELLS.

&&

.CLIMATE...THE RECORD HIGH FOR TODAY IS ONLY 92F AND TEMPS LIKELY TO
CLIMB AGAIN IN THE MID 90S UNDER SHORTWAVE RIDGE ALOFT AND SOUTHERLY
DOWNSLOPE FLOW.

&&

.PRELIMINARY POINT TEMPS/POPS...
SJU  92  76  92  75 /  10  10  20  10
STT  85  77  85  78 /  10  20  20  10

&&

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

$$

25/23




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