Prognostic Meteorological Discussion
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FXCA20 KWBC 121856
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TROPICAL DISCUSSION - INTERNATIONAL DESKS
NWS WEATHER PREDICTION CENTER COLLEGE PARK MD
156 PM EST FRI FEB 12 2016

TROPICAL DISCUSSION FROM FEBRUARY 11/12 UTC: MID/UPPER LEVEL
TROUGH OVER THE EASTERN USA/WESTERN ATLANTIC CONTINUES TO DEEPENS
UNDER INFLUENCE OF PROGRESSIVE SHORT WAVE PERTURBATION ROUNDING
THE LONG WAVE AXIS. THE TROUGH REACHES MAXIMUM AMPLITUDE OVER THE
NEXT DAY OR SO...THEN STARTS TO LIFT OVER A RIDGE TO THE EAST.
BASE OF THE MID LEVEL TROUGH IS TO THEN SWEEP THE NORTHERN
CARIBBEAN ISLES...CROSSING PUERTO RICO/VIRGIN ISLES-NORTHERN
LEEWARD LATER ON SUNDAY. AS IT MEANDERS ACROSS THE NORTHERN
CARIBBEAN ISLES WEAK CYCLONIC VORTICES ARE TO STREAM ACROSS THE
ISLANDS. AT 250 HPA... MEANWHILE...A SUBTROPICAL JET MAXIMA WILL
BOUND THE SOUTHERN FRINGES OF THE LONG WAVE TROUGH. THIS WILL
SLOWLY PROPAGATE TO THE EAST WHILE REMAINING NORTH OF THE ISLANDS.
WEAK CONVERGENCE ON ITS RIGHT EXIT REGION IS EXPECTED AS IT PULLS
NORTH OF THE GREATER ANTILLES...WITH UPPER LEVEL ENVIRONMENTAL
CONDITIONS FORECAST TO REMAIN HOSTILE TO ORGANIZED DEEP CONVECTION.

AT LOW LEVELS...A WANING FRONT EXTENDS ACROSS THE
SOUTHEAST/CENTRAL BAHAMAS-CUBA TO THE WESTERN CARIBBEAN. THE FRONT
IS FORECAST TO FRONTOLIZE LATER TODAY/EARLY SATURDAY MORNING. AS
IT WEAKENS...A NEW FRONT IS TO GRADUALLY PROPAGATE ACROSS NORTH
FLORIDA/SOUTHERN USA LATER TODAY. THROUGH SATURDAY MORNING THE
FRONT MOVES INTO CENTRAL FLORIDA...AND IN THE EVENING IT IS TO
ENTER THE NORTHWEST BAHAMAS. THROUGH SUNDAY MORNING THE FRONT
MEANDERS ACROSS THE CENTRAL BAHAMAS WHILE TRAILING END REMAINS
OVER THE GULF. THIS IS TO REMAIN NEARLY STATIONARY THROUGH SUNDAY
EVENING...THEN STARTS TO RETROGRESS ACROSS THE CENTRAL TO
NORTHWEST BAHAMAS-SOUTH FLORIDA. ON SATURDAY A BUILDING POLAR
RIDGE TO THE WEST IS TO TRIGGER ANOTHER SHEAR LINE AND STRONG LOW
LEVEL WINDS ACROSS THE WESTERN-CENTRAL CARIBBEAN. THE SHEAR LINE
MOVES TO THE SOUTHEAST BAHAMAS-EASTERN CUBA-NORTHERN HONDURAS
EARLY ON SATURDAY MORNING...TRAILING TO NORTHEAST NICARAGUA LATER
ON SATURDAY. DURING THE MORNING ON SUNDAY IT PULLS ACROSS
HISPANIOLA-JAMAICA TO NORTHEAST NICARAGUA. ON SUNDAY EVENING IT
MOVES ACROSS HISPANIOLA WHILE TRAILING END REMAINS OVER NORTHEAST
NICARAGUA. LOW LEVEL WINDS ACROSS THE WESTERN-CENTRAL CARIBBEAN
WILL PEAK AT 20-25KT...WITH TOPOGRAPHICALLY ENHANCED CONVECTION
FORECAST TO AFFECT NORTHERN HONDURAS. AS THE FRONT MEANDERS OVER
THE BAHAMAS...THIS IS TO FAVOR SCATTERED RAINS LATER ON
SUNDAY...WITH ACCUMULATION OF 00-05MM/DAY AND ISOLATED MAXIMA OF
10MM. OVER THE SOUTHEAST BAHAMAS-TURKS AND EASTERN CUBA...THE
SHEAR LINE WILL SUSTAIN RAINFALL AMOUNTS OF 10-15MM/DAY AND MAXIMA
OF 20-35MM ON SATURDAY. ACROSS JAMAICA THIS WILL RESULT IN
RAINFALL AMOUNTS OF 10-15MM/DAY AND MAXIMA OF 20-40MM. STRONG
NORTHERLIES ACROSS THE WESTERN CARIBBEAN ARE TO ALSO FAVOR
TOPOGRAPHICALLY INDUCED CONVECTION ACROSS NORTHERN HONDURAS. THIS
STARTS LATER ON FRIDAY/EARLY SATURDAY MORNING WITH RAINFALL
AMOUNTS 15-30MM/DAY AND MAXIMA OF 40-80MM...DECREASING TO
05-10MM/DAY AND MAXIMA OF 15-20MM ON SUNDAY TO MONDAY. ACROSS
NORTHERN HISPANIOLA THE SHEAR LINE WILL SUSTAIN RAINFALL AMOUNTS
OF 05-10MM/DAY AND MAXIMA OF 15MM DURING THE DAY ON SUNDAY. ACROSS
PUERTO RICO/VIRGIN-LEEWARD ISLES...A PREFRONTAL/INDUCED INVERTED
TROUGH WILL FAVOR LIGHT CONVECTION ON SUNDAY TO MONDAY...WITH
RAINFALL AMOUNTS OF 00-05MM/DAY AND MAXIMA OF 10MM.

FARTHER EAST...A 500 HPA HIGH NEAR 30N 35W ANCHORS A RIDGE ACROSS
THE EASTERN-CENTRAL CARIBBEAN. AS THE AFOREMENTIONED TROUGH
PROPAGATES ACROSS THE WESTERN ATLANTIC-NORTHERN CARIBBEAN ISLES IT
IS TO PRESS AGAINST THIS AXIS...FAVORING GRADUAL EROSION OF MID
LEVEL RIDGE PATTERN THROUGH SUNDAY EVENING. ALTHOUGH THE RIDGE
TENDS TO WEAKEN...A WEAK TRADE WINDS CAP IS TO PERSIST ACROSS THE
ISLAND CHAIN-NORTHERN SOUTH AMERICA.

SOUTH OF THE SUBTROPICAL RIDGE...A RETROGRESSING TUTT LOW LIES
NORTH OF SURINAME/GUYANA...WITH AXIS TO MEANDER WEST ACROSS THE
GRENADINES/WINDWARD ISLES LATER TODAY. THIS FEATURE...HOWEVER...IS
TO CONFINE TO ATMOSPHERE ABOVE 500 HPA...THUS HAVING LITTLE TO NO
IMPACT AS IT PULLS INTO THE SOUTHEAST CARIBBEAN. ANOTHER TUTT LIES
TO THE SOUTH...WITH AXIS WEST ACROSS NORTHERN BRASIL ALONG 05S.
THIS TROUGH IS ENHANCING CONVECTION ACROSS EQUATORIAL SOUTH
AMERICA. OVER PORTIONS OF FRENCH GUIANA THIS IS TO FAVOR RAINFALL
AMOUNTS OF 05-10MM/DAY AND MAXIMA OF 15-25MM...WHILE OVER SOUTHERN
COLOMBIA AND VENEZUELA EXPECTING RAINFALL AMOUNTS OF 05-10MM/DAY
AND MAXIMA OF 15MM. BRISK NORTHEASTERLY WINDS OVER THE SOUTHERN
CARIBBEAN/SOUTHERN CENTRAL AMERICA DISPLACED THE EASTERN PACIFIC
ITCZ SOUTH TO THE CAUCA VALLEY IN SOUTHWEST COLOMBIA...WHERE IT IS
TO FAVOR RAINFALL AMOUNTS OF 05-10MM/DAY AND MAXIMA OF 15MM/DAY.
ON SATURDAY...HOWEVER...THIS INCREASES TO 10-15MM/DAY AND MAXIMA
OF 20-40MM.

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

HUNTE...BMS (BARBADOS)
DAVISON/GALVEZ...WPC (USA)
$$





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