TROPICAL DISCUSSION - INTERNATIONAL DESKS
NWS WEATHER PREDICTION CENTER COLLEGE PARK MD
943 AM EDT THU MAY 16 2013

PRELIMINARY DISCUSSION FOR PUERTO RICO AND THE USVI. MID/UPPER
LEVEL TROUGH OVER THE NORTHERN CARIBBEAN IS ORGANIZED IN TWO SHORT
WAVES. ONE OVER HISPANIOLA AND THE OTHER TO THE EAST OVER PUERTO
RICO AND INTO NORTHERN VENEZUELA. UPPER CONVERGENCE IS
ESTABLISHING TO THE NORTH OF HISPANIOLA LIMITING VERTICAL
DEVELOPMENT TO THE NORTH OF 20N. AT LOW LEVELS...A REGION OF TRADE
WIND CONVERGENCE EXTENDS ACROSS THE NORTHERN CARIBBEAN INTO
SOUTHERN HISPANIOLA...WHERE THE STRONGEST CONVECTION WAS ORGANIZED.

UPPER TROUGH WILL CONTINUE MOVING ACROSS THE NORTHEAST CARIBBEAN
ISLES WHILE STARTING TO FLATTEN. FORECAST AREA IS TO GRADUALLY
ENTER THE UPPER CONVERGENT TIER OF THE JET...WITH CAP INVERSION
FORECAST TO STRENGTHEN THROUGH FRIDAY EVENING. AT LOW
LEVELS...LIGHT EASTERLY TRADES ARE TO PREVAIL OVER THE NEXT TWO
DAYS...WHILE AT 700 HPA MEANDERING WINDS ARE EXPECTED DURING THE
CYCLE. LOWER-RESOLUTION MODELS ARE SUGGESTING A LOW ACCUMULATIONS
TODAY...WHILE HIGHER RESOLUTION ONES STILL SUGGEST SOME LOCALIZED
MODERATE ACCUMULATIONS LATER TODAY. LOW-LEVEL CONVERGENCE AND
CONVECTIVE WILL REMAIN ENHANCED COMPETING WITH STRENGTHENING CAP.
THIS WILL LEAD TO A FEW ISOLATED MODERATE SHOWERS AND ISOLATED
THUNDERSTORMS ACROSS THE CORDILLERA AND NORTHWEST PORTIONS OF
PUERTO RICO...WITH RAINFALL AMOUNTS OF 05-10MM/DAY AND MAXIMA TO
GENERALLY PEAK AT 15-20MM. IN A WEAK STEERING FLOW
PATTERN...LOCALIZED MAXIMA OF 25-50MM ARE
POSSIBLE...BUT WILL TEND TO BE AGAIN QUITE SPARSE AND FEW WITH
LITTLE CHANCE FOR SECONDARY REGENERATION.

BLENMAN...BMS (BARBADOS)
MCKENZIE...BDM (BAHAMAS)
DAVISON/GALVEZ...WPC (USA)