Prognostic Meteorological Discussion
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FXCA20 KWBC 281025
PMDCA

TROPICAL DISCUSSION - INTERNATIONAL DESKS
NWS WEATHER PREDICTION CENTER COLLEGE PARK MD
625 AM EDT TUE APR 28 2015

PRELIMINARY DISCUSSION FOR PUERTO RICO AND THE USVI FROM APRIL
28/06 UTC: NO CHANGES TO THE FORECAST AS MID/UPPER LEVEL RIDGE
CONTINUES TO DOMINATE FORECAST AREA. THIS CONTINUES TO FAVOR A
STRONG CAP INVERSION AND GENERALLY DRY AND STABLE CONDITIONS. AT
LOW LEVELS...RIDGE TO THE EAST SUSTAINS A SOUTH-SOUTHEASTERLY FLOW
ACROSS THE FORECAST AREA. IN A TIGHT GRADIENT...TRADES ARE SURGING
ACROSS THE TROPICAL ATLANTIC...WITH THE RGB DUST PRODUCT SHOWING A
SAHARAN AIR LAYER QUICKLY PROPAGATING TOWARDS THE LESSER ANTILLES.

MID/UPPER LEVEL RIDGE PATTERN IS TO REMAIN NEARLY UNCHANGED DURING
THE NEXT THREE DAYS...WITH GRADUAL EROSION LATER IN THE WEEK AS A
POLAR TROUGH DEEPENS ACROSS THE EASTERN USA INTO THE WESTERN
ATLANTIC. MEANWHILE...STATUS QUO IS TO PERSIST...WITH A SHARP DROP
IN PWAT CONTENT EXPECTED LATER ON WEDNESDAY AS THE SAL AIR MASS
ENTERS THE FORECAST AREA. AS LOW LEVEL RIDGE HOLDS TO THE
EAST...SOUTHERLY WIND AND ABOVE NORMAL TEMPERATURES ARE TO PERSIST
THROUGH SUNDAY MORNING. GLOBAL MODELS AGREE ON MOSTLY DRY AND
STABLE CONDITIONS TO PERSIST DURING THIS PERIOD...WITH A GLIMMER
OF HOPE THAT PATTERN MIGHT CHANGE LATER DURING THE WEEKEND.

DISCUSSION FROM APRIL 28/12 UTC:


TROPICAL/EASTERLY WAVES INITIALIZED AT 12UTC
INITIAL  24     36     48     60     72     84     96        TYPE
NONE

CRAIG...TTMS (TRINIDAD AND TOBAGO)
SAMUEL...MDS (SURINAME)
DAVISON...WPC (USA)
GALVEZ...WPC (USA)
$$





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