Prognostic Meteorological Discussion
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FXCA20 KWBC 221059
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TROPICAL DISCUSSION - INTERNATIONAL DESKS
NWS WEATHER PREDICTION CENTER COLLEGE PARK MD
658 AM EDT WED OCT 22 2014

PRELIMINARY DISCUSSION FOR PUERTO RICO AND THE USVI. AT UPPER
LEVELS...A TUTT NOW EXTENDS FROM WESTERN PUERTO RICO/MONA PASSAGE
TO THE GULF OF URABA/NORTHERN PANAMA. THIS IS PRESSING AGAINST A
WANING RIDGE TO THE EAST AS THE LATTER EXTENDS FROM VENEZUELA TO
THE EASTERN CARIBBEAN. AT LOW LEVELS...A TROPICAL WAVE EXTENDS
ALONG 56W/57W. MOST ACTIVE CONVECTION WITH THIS FEATURE IS
BUILDING ALONG THE ITCZ AND SOUTHWARD INTO GUYANA/NORTHEAST
VENEZUELA.

BUILDING RIDGE ALOFT IS TO DISPLACE THE TUTT ACROSS THE FORECAST
AREA THROUGH THE DAY TODAY...AND EARLY ON FRIDAY IT IS TO SETTLE
ACROSS THE FRENCH/WINDWARD ISLANDS TO NORTHEAST VENEZUELA. THIS
TROUGH IS TO GRADUALLY STRENGTHEN LATER DURING THE WEEKEND...WHEN
A DEEP CLOSED LOW FORMS OVER THE FRENCH ISLANDS. AT MID LEVELS
THIS IS TO THEN FAVOR AN INVERTED TROUGH ACROSS THE ISLAND
CHAIN/EASTERN CARIBBEAN...BUT THIS IS TO GENERALLY REMAIN EAST OF
THE FORECAST AREA. AS THE TROUGH ALOFT SWINGS ACROSS THE NORTHEAST
CARIBBEAN ISLES...AN UPPER CONVERGENT PATTERN IS TO ESTABLISH.
THIS IS TO SUSTAIN A FAIRLY STRONG CAP INVERSION THROUGH AT LEAST
FRIDAY MORNING...IF NOT LONGER. AS THE INVERSION STRENGTHENS...IT
IS TO THEN FAVOR A PWAT MINIMA. THIS WILL TEND TO FAVOR FAIR
WEATHER CONDITIONS ACROSS THE NORTHEAST CARIBBEAN ISLES...WITH
DIURNAL CONVECTION TO LIKELY LIMIT TO NORTHWEST PORTIONS OF PUERTO
RICO.

AT LOW LEVELS...THE TROPICAL WAVE IS TO TRACK SOUTH OF THE
FORECAST AREA...MOVING ACROSS 65W/66W BY FIRST LIGHT ON
FRIDAY...AND LATER IN THE DAY MOVING ACROSS 68W/69W. IN A
CONVERGENT PATTERN ALOFT...HOWEVER...THE MOST ACTIVE CONVECTION IS
EXPECTED FAR TO THE SOUTH. A FEW CELLS MIGHT REACH SAINT
CROIX-SOUTHEAST COAST OF PUERTO RICO...BUT FOR THE MOST PART THE
GLOBAL MODELS AGREE ON LIGHT TO TRACE RAINFALL AMOUNTS.

JN BAPTISTE...MS (SAINT LUCIA)
MEDINA...ONAMET (REPUBLICA DOMINICANA)
DAVISON...WPC (USA)

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