370
FXCA20 KWBC 141248
PMDCA
TROPICAL DISCUSSION - INTERNATIONAL DESKS
NWS WEATHER PREDICTION CENTER COLLEGE PARK MD
747 AM EST TUE FEB 14 2023
PRELIMINARY DISCUSSION FOR PUERTO RICO AND THE USVI FROM FEB
14/12UTC: OUT OF THE NEXT FIVE DAYS...TODAY IS EXPECTED TO BE THE
DAY WITH THE HIGHEST RAINFALL ACCUMULATIONS ACROSS CENTRAL TO
WESTERN PUERTO RICO...OVER 1 INCH OF RAIN IS POSSIBLE THIS
AFTERNOON. NORTHERN AND EASTERN PUERTO RICO WILL HAVE SCATTERED
SHOWERS OVER THE NEXT SEVERAL DAYS...POSSIBLY AMOUNTING TO OVER
0.25 INCHES EACH DAY...WHILE THE USVI CAN EXPECT A FEW HUNDREDTHS
OF AN INCH OF RAIN EACH DAY.
A SURFACE HIGH PRESSURE ACROSS THE NORTH CENTRAL ATLANTIC IS
CAUSING EASTERLY WINDS THIS MORNING ACROSS THE NORTHEASTERN
CARIBBEAN. HOWEVER...A SURFACE LOW PRESSURE ACROSS THE
NORTHWESTERN ATLANTIC AND A FRONTAL BOUNDARY...THAT EXTENDS FROM
THE LOW PRESSURE CENTER TO THE BAHAMAS...WILL MOVE EAST AND WEAKEN
THE LOCAL PRESSURE GRADIENT...CAUSING THE LOCAL WINDS TO WEAKEN.
THIS DECREASE IN WINDS WILL ALLOW FOR SEA BREEZE CONVERGENCE TO
DEVELOP ACROSS CENTRAL TO WESTERN PR BY THE EARLY AFTERNOON HOURS.
IN ADDITION...A PATCH OF MOISTURE WILL MOVE IN DURING THE
DAY...WHICH WILL COMBINE WITH THE SEA BREEZE CONVERGENCE AND
DIURNAL HEATING. ALL OF WHICH WILL CONTRIBUTE TO THE DEVELOPMENT
OF SHOWER ACTIVITY THIS AFTERNOON ACROSS CENTRAL TO WESTERN PR.
SINCE THE WINDS ARE RELATIVELY LIGHT...THE SHOWER ACTIVITY IS
EXPECTED TO MOVE SLOWLY...WHICH THEN CAN CAUSE ACCUMULATIONS OF
OVER 1 INCH OF RAIN IN SOME AREAS. OTHER AREAS OF PUERTO
RICO...ESPECIALLY ACROSS THE NORTHEASTERN AND EASTERN
SECTIONS...COULD OBSERVE 0.25 TO 0.5 INCHES OF RAIN WITH SCATTERED
SHOWERS. AT THIS TIME...THE COASTAL SOUTH AND NORTH OF PUERTO RICO
IS EXPECTED TO HAVE THE LOWEST RAINFALL ACCUMULATIONS...IF ANY.
THE MID LEVELS WILL BE DOMINATED BY A HIGH PRESSURE...WHICH WILL
INHIBIT DEEP CONVECTION. THAT SAID...THE RELATIVE HUMIDITY AT THE
LOW TO MID LEVELS WILL INCREASE TO ABOVE NORMAL LEVELS...EVEN
THOUGH THE PRECIPITABLE WATER INCREASE EXPECTED WILL BE NEAR TO
SLIGHTLY ABOVE NORMAL...AT AROUND 1.5 INCHES. THE PATCH OF
MOISTURE EXPECTED TODAY WILL HAVE THE HIGHEST PRECIPITABLE WATER
VALUE OF THE NEXT 5 DAYS...PRECIPITABLE WATER COULD BE AT 1.2
INCHES OR LOWER FROM WEDNESDAY ONWARD.
FROM WEDNESDAY ONWARD...THE LOCAL WINDS ARE EXPECTED TO SHIFT TO A
MORE NORTHEASTERLY DIRECTION...AS ANOTHER SURFACE HIGH PRESSURE
MOVES INTO THE WESTERN ATLANTIC. THE LOCAL WINDS WILL ALSO
INCREASE...AT 10-15KT ON WEDNESDAY...THEN AROUND 20KT ON THURSDAY
AND FRIDAY...THEN DOWN TO AROUND 15-20KT ON SATURDAY. THIS WIND
DIRECTION AND SPEED...COMBINED WITH THE SLIGHTLY BELOW NORMAL
MOISTURE AND MID LEVEL RIDGE...WILL BRING BACK THE TYPICAL PATTERN
OF ISOLATED TO SCATTERED SHOWERS ACROSS THE NORTHEAST
CARIBBEAN...CAUSING SOME RAINFALL ACROSS NORTH AND EASTERN PR IN
THE MORNING AND EVENING HOURS AS WELL AS THE USVI. AFTERNOON
CONVECTION WOULD BE LIMITED...AND IT WOULD BE ACROSS SOUTHWESTERN
PR.
ALAMO/ACOSTA...WPC (USA)
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