793 
FXCA62 TJSJ 110114 AAA
AFDSJU

AREA FORECAST DISCUSSION...UPDATED
NATIONAL WEATHER SERVICE SAN JUAN PR
914 PM AST MON JUN 10 2013

.UPDATE...THE 11/00Z SOUNDING CAME IN WITH SIMILAR MOISTURE TO THE
10/12Z SOUNDING AND WAS WETTER THAN 24 HOURS AGO WITH 1.93 INCHES
OF PRECIPITABLE WATER. HIGH CLOUDS HAVE DOMINATED THE SKIES OVER
THE LOCAL AREA AS A SOUTHWEST JET CONTINUES OVER THE AREA WITH 50
KNOT PLUS WINDS AT 46 KFT. CONVECTIVE ACTIVITY HAS COMPLETELY DIED
OUT OVER LAND AND A FEW NARROW BANDS OF SHOWERS ARE MOVING WEST
ACROSS THE CARIBBEAN. IT IS UNLIKELY THAT THESE WILL MAKE IT
ACROSS THE SOUTHERN PART OF PUERTO RICO WITH MUCH STRENGTH
ESPECIALLY SINCE BUOY 42085 AND OTHER LAND STATIONS SHOW SOME
OFFSHORE COMPONENT. LATEST GFS FORECAST OF PRECIPITABLE WATER
SUGGESTS AN INCREASE TO OVER 2 INCHES AGAIN TOMORROW AFTERNOON AND
EVENING...ALTHOUGH MOISTURE WAS SUPPOSED TO DECREASE OVERNIGHT
THEREFORE HAVE BUMPED POPS UP SOMEWHAT OVER PUERTO RICO...AS LAST
SEVERAL DAYS HAVE SEEN HEAVY SHOWERS...THOUGH LITTLE FLOODING AND
LITTLE HAS CHANGED. OTHERWISE DISCUSSION BELOW HOLDS UP WELL.
LOOKING AHEAD TO THE WEEKEND...THE NAAPS FORECAST IS SHOWING ONE
OF THE MORE SIGNIFICANT DUST EVENTS OF THIS YEAR SHAPING UP FOR
SATURDAY AND SUNDAY. THIS MODEL SOMETIMES OVER-FORECASTS BUT DO
EXPECT MORE THAN TODAY OR YESTERDAY THEN.


&&

.AVIATION...VFR CONDITIONS EXPECTED TO PREVAIL AT ALL TAF SITES 
WITH A FEW LIGHT ISOLATED SHOWERS THROUGH 11/12Z.  LOW LEVEL WINDS 
FROM THE EAST AT 5 TO 15 KNOTS OVERNIGHT. NOTE...ASOS READINGS OF
MVFR CEILINGS ARE SUSPECT DUE TO HIGHER CONCENTRATIONS OF SAHARAN
DUST AND TAFS WRITTEN TO REFLECT THIS.

&&

.MARINE...SEAS AT BUOY 41043 HAVE BEEN BELOW 7 FEET SINCE BEFORE
10/12Z AND LOCAL AREAS ARE SHOWING 4 TO 5 FEET. SMALL CRAFT STILL
NEED TO EXERCISE CAUTION FOR WINDS OF 15 TO 20 KNOTS AND SOME SEAS
AROUND 6 FEET IN OUTER WATERS.

&&

.PREV DISCUSSION... /ISSUED 303 PM AST MON JUN 10 2013/ 

SYNOPSIS...SURFACE HIGH PRESSURE OVER THE CENTRAL ATLANTIC IS
EXPECTED TO REMAIN THERE FOR THE NEXT FEW DAYS...CAUSING MODERATE
TO FRESH TRADE WINDS WINDS ACROSS THE LOCAL AREA. UPPER TROUGH
NORTH OF HISPANIOLA WILL SLOWLY MOVE TO THE NORTHEAST AND NORTH OF
OUR LOCAL AREA AS IT WEAKENS BY WEDNESDAY. SOME SAHARAN DUST
EXPECTED LATE WEDNESDAY AND A TROPICAL WAVE WILL MOVE OVER THE
AREA ON FRIDAY.

DISCUSSION...SCATTERED TO LOCALLY NUMEROUS SHOWERS WITH ISOLATED
THUNDERSTORMS DEVELOPED ACROSS THE LOCAL AREA. THE THUNDERSTORMS
WERE MOSTLY LIMITED TO THE SOUTHWESTERN QUADRANT OF PUERTO RICO AS THE
AVAILABLE MOISTURE COMBINED WITH DIURNAL HEATING AND SEA BREEZE
CONVERGENCE. HOWEVER...A FEW OF THE PASSING SHOWERS DID HAVE
THUNDER AND LIGHTNING FOR A FEW MINUTES.

AVAILABLE MOISTURE IS EXPECTED TO INCREASE ACROSS THE CARIBBEAN
WATERS DURING THE OVERNIGHT HOURS AS IT SLOWLY MOVES NORTH ON
TUESDAY. THIS WILL CAUSE SHOWERS ONCE AGAIN ACROSS PUERTO
RICO...WITH THUNDERSTORMS EXPECTED IN THE WESTERN SECTIONS OF
PUERTO RICO ONCE AGAIN. SOME SAHARAN DUST WILL BE MAKING ITS WAY
IN ON WEDNESDAY INTO THURSDAY...CAUSING SOME HAZY SKIES JUST
BEFORE A TROPICAL WAVE COMES IN ON FRIDAY...INCREASING AVAILABLE
MOISTURE SIGNIFICANTLY AS WELL AS 850MB THETA-E. SHOWER AND
THUNDERSTORM ACTIVITY IS QUITE POSSIBLE AS THIS WAVE PASSES.

AVIATION...VFR CONDITIONS EXPECTED TO PREVAIL AT ALL TAF SITES
WITH A FEW SHOWERS AND ISOLATED THUNDERSTORMS IN THE VICINITY OF
TJMZ THROUGH ABOUT 10/21Z. FAST MOVING SHOWERS ARE POSSIBLE FROM
TIME TO TIME AT TNCM/TIST/TISX AND TJSJ. LOW LEVEL WINDS FROM THE
EAST AT 10 TO 20 KNOTS.

MARINE...MAIN HAZARD WILL BE SHOWERS AND THUNDERSTORMS OVER THE
WATERS...SEAS WILL BE UP TO 6 FEET AND WINDS UP TO 20 KNOTS. SMALL
CRAFT SHOULD EXERCISE CAUTION.

&&

.PRELIMINARY POINT TEMPS/POPS...
SJU  77  88  77  88 /  40  40  40  40 
STT  79  88  79  89 /  30  30  30  30 

&&

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

$$

15/12