Prognostic Meteorological Discussion
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FXCA20 KWBC 232131
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TROPICAL DISCUSSION - INTERNATIONAL DESKS
NWS WEATHER PREDICTION CENTER COLLEGE PARK MD
431 PM EST THU FEB 23 2017

TROPICAL DISCUSSION FROM FEB 23/12 UTC: UNUSUALLY STRONG MID-UPPER
LOW EXITING THE FLORIDA PENINSULA IS INDUCING A SURFACE COLD FRONT
THAT EXTENDS INTO CENTRAL PARTS OF CENTRAL AMERICA. BY THURSDAY
EVENING...THE FRONT WILL EXTEND ACROSS THE SOUTHEASTERN
BAHAMAS...SOUTHEASTERN CUBA...JUST EAST OF JAMAICA...NORTHEASTERN
NICARAGUA. LARGEST RAINFALL AMOUNTS ARE TO CONCENTRATE IN THE
CENTRAL AND SOUTHEASTERN BAHAMAS WHERE EXPECTING 10-15MM/DAY AND
MAXIMA OF 20-40MM. IN THE NORTHWESTERN BAHAMAS EXPECTING MAXIMA OF
15-20MM. IN SOUTHEASTERN CUBA...SOUTH OF THE SIERRA
MAESTRA...EXPECTING ISOLATED MAXIMA OF 20-40MM/DAY UNDER
OROGRAPHIC FORCING. IN JAMAICA EXPECTING MAXIMA OF 15MM...AND
15-20MM/DAY IN AREAS SOUTHERN SLOPES WHERE OROGRAPHIC FORCING IS
SIGNIFICANT. BY FRIDAY EVENING AN ILL-DEFINED TAIL OF THE FRONT
WILL EXTEND INTO THE SOUTHEASTERN BAHAMAS. STRONGEST CONVECTION
WILL CONCENTRATE OVER THE SOUTHEASTERN BAHAMAS WHERE EXPECTING
05-10MM/DAY AND MAXIMA OF 15-20MM. IN SOUTHERN CUBA AND THE
SOUTHERN HAITIAN PENINSULA EXPECTING MAXIMA OF 10MM. THE FRONT IS
EXITING THE FORECAST DOMAIN WHILE IT WEAKENS ON SATURDAY.

UNDER THE INFLUENCE OF THE AFOREMENTIONED UPPER TROUGH AND
FRONT...MODELS AGREE ON A REVERSAL OF THE TRADES IN THE PACIFIC
COAST OF NORTHERN CENTRAL AMERICA BY THURSDAY INTO THE WEEKEND.
ALTHOUGH MOISTURE IS LIMITED...EXPECTING THE DEVELOPMENT OF RAIN
SHOWERS IN PACIFIC BASINS OF GUATEMALA/EL SALVADOR/HONDURAS AND
NICARAGUA...WHERE EXPECTING AMOUNTS OF 05-10MM/DAY AND ISOLATED
MAXIMA OF 15MM INITIALLY...DECREASING TO MAXIMA OF 10MM
AFTERWARDS. UNDER THE PRESENCE OF WEAK WINDS...EXPECTING DIURNAL
BREEZES TO DOMINATE. IN COSTA RICA...EXPECTING ALSO CONVECTION
EXTENDING INTO THE PACIFIC BASIN WITH ACCUMULATIONS OF 05-10MM/DAY
AND VERY ISOLATED MAXIMA OF 15-25MM THROUGH THE CYCLE.

POTENT UPPER TROUGH IS EXITING THE DOMAIN ACROSS THE NORTHEASTERN
CARIBBEAN. ALTHOUGH THE TROUGH IS LOSING DIRECT INFLUENCE IN THE
WEATHER ACROSS THE CARIBBEAN...THE ASSOCIATED UPPER JET IS
ENHANCING ACTIVITY ACROSS THE GUIANAS. FURTHERMORE...THIS HAS
UNDULATED THE ITCZ NORTHWARD AND IS BUILDING A MOISTURE POOL
OVER/JUST TO THE NORTH OF THE GUIANAS THAT WILL ENHANCE ACTIVITY
ACROSS NORTHERN SOUTH AMERICA AS THE CYCLE PROGRESSES. THROUGH
EARLY FRIDAY...EXPECTING MAXIMA OF 25-50MM ACROSS FRENC GUIANA AND
MAXIMA OF 30-60MM/DAY ACROSS GUYANA INTO SOUTHERN VENEZUELA.
AMOUNTS ARE TO DECREASE TO MAXIMA OF 15-20MM/DAY IN GUYANA BY
FRIDAY-SATURDAY...WHILE IN NORTHEASTERN VENEZUELA EXPECTING AN
INCREASE TO MAXIMA OF 15MM. BY SATURDAY-SUNDAY EXPECTING MAXIMA OF
15MM IN THE GUIANAS. ALONG THE NORTHERN COAST OF VENEZUELA
EXPECTING MAXIMA OF 10MM. N INCREASE IN DEEP-LAYER MOISTURE IN THE
COLOMBIAN LLANOS AND ANDES WILL LEAD TO MAXIMA OF 25-50MM/DAY IN
THE LOWLANDS...AND MAXIMA OF 20-30MM/DAY IN THE ANDEAN REGION.

TROPICAL/EASTERLY WAVES INITIALIZED AT 12UTC:
INITIAL   24     36     48     60     72     84     96    TYPE
51W      54W    57W   DISS                                 EW

A WEAK WEAVE IN THE TRADES IS ENHANCING CONVECTION IN FRENCH
GUYANA ON THURSDAY AND IS FORECAST TO LOSE DEFINITION AS IT MOVES
INTO THE CONTINENT.

JIMENEZ...IMN (COSTA RICA)
SUBRATH-ALI...TTMS (TRINIDAD AND TOBAGO)
GALVEZ...WPC (USA)

$$




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