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AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE SAN JUAN PR
233 PM AST SAT AUG 29 2015

.SYNOPSIS...HIGH PRESSURE NORTH OF THE ISLANDS WILL KEEP A
MODERATE EASTERLY WIND FLOW FOR THE NEXT SEVERAL DAYS. TWO
TROPICAL WAVES ARE EXPECTED TO AFFECT THE REGION. FIRST TROPICAL
WAVE WILL AFFECT THE REGION ON SUNDAY AND THE NEXT ONE WILL PASS
THROUGH THE AREA TUESDAY INTO WEDNESDAY.

&&

.DISCUSSION...A STABLE AIR MASS MOVED ACROSS THE REGION
TODAY..LIMITING THE SHOWER ACTIVITY ACROSS THE REGION. IN
FACT...VERY LITTLE ACTIVITY WAS OBSERVED. 

A WEAK TROPICAL WAVE IS EXPECTED TO MOVE OVER THE REGION EARLY
SUNDAY MORNING...BRINGING AN INCREASE IN LOW LEVEL MOISTURE TO THE
LOCAL AREA. GFS MODEL GUIDANCE SUGGESTS THAT THE PWAT VALUES WILL
INCREASE UP TO 2.2 INCHES BUT THE BULK OF THE MOISTURE ASSOCIATED
WITH THE WAVE IS EXPECTED TO REMAINS SOUTH OF THE LOCAL ISLANDS
ACROSS THE CARIBBEAN WATERS. AFTER THE PASSAGE OF THIS
WAVE...RELATIVELY DRY WEATHER CONDITIONS ARE EXPECTED ON MONDAY.
ANOTHER TROPICAL WAVE IS EXPECTED TO AFFECT THE LOCAL REGION BY
TUESDAY. THIS WAVE WILL BRING BETTER MOISTURE TO THE LOCAL AREA
COMPARED TO THE WAVE WHICH WILL AFFECT US TOMORROW. IN THE LONG
TERM..AT THIS TIME...NO OTHER SIGNIFICANT WEATHER EVENTS ARE
FORECAST TO AFFECT THE LOCAL REGION.

&&

.AVIATION...A TROPICAL WAVE WILL CONTINUE TO MOVE WESTWARD 
ACROSS THE LESSER ANTILLES THIS EVENING AND ACROSS THE USVI AND 
PUERTO RICO OVERNIGHT AND EARLY SUNDAY. THIS FEATURE WILL PRODUCE 
BRIEF PERIODS OF MVFR CONDITIONS ACROSS TKPK AND TNCM AFTER 
29/22Z...ACROSS TISX AND TIST AFTER 30/03Z AND ACROSS TJSJ AND TJPS 
AFTER 30/06Z. THE MOISTURE ASSOCIATED WITH THE WAVE IS EXPECTED 
PRODUCE MVFR OR EVEN IFR CONDITIONS OVER TJMZ AND TJBQ IN SHRA AND 
TSRA FROM 30/17Z TO 30/21Z. WINDS WERE MOSTLY FROM THE EAST 
SOUTHEAST AT 10 TO 15 MPH WITH SOME HIGHER GUSTS.

&&

.MARINE...SEAS WILL REMAIN CHOPPY THE REST OF THIS AFTERNOON AND
TONIGHT WITH WINDS OF 18 KNOTS AND HIGHER GUSTS. SEAS WILL
GRADUALLY IMPROVE TONIGHT BUT THEY STILL ARE UP TO 6 FEET. SMALL
CRAFT SHOULD EXERCISE CAUTION. A HIGH RISK OF RIP CURRENTS WILL
REMAIN ACROSS MANY OF THE LOCAL BEACHES...PLEASE REFER TO THE RIP
CURRENT STATEMENT FOR MORE DETAILS.


&&

.PRELIMINARY POINT TEMPS/POPS...
SJU  81  89  81  90 /  40  40  10  30 
STT  81  89  80  90 /  40  40  30  30 

&&

.SJU WATCHES/WARNINGS/ADVISORIES...
PR...HIGH RIP CURRENT RISK UNTIL 6 PM AST THIS EVENING FOR NORTH 
     CENTRAL-NORTHEAST-NORTHWEST-SAN JUAN AND VICINITY-SOUTHEAST-
     SOUTHWEST-VIEQUES-WESTERN INTERIOR.

VI...HIGH RIP CURRENT RISK UNTIL 6 PM AST THIS EVENING FOR ST CROIX.

AM...HIGH RIP CURRENT RISK UNTIL 6 PM AST THIS EVENING FOR COASTAL 
     WATERS OF SOUTHWESTERN PUERTO RICO OUT 10 NM.

&&

$$

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