Prognostic Meteorological Discussion
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FXCA20 KWBC 111914
PMDCA

TROPICAL DISCUSSION - INTERNATIONAL DESKS
NWS WEATHER PREDICTION CENTER COLLEGE PARK MD
213 PM EST THU FEB 11 2016

TROPICAL DISCUSSION FROM FEBRUARY 11/12 UTC: PERSISTENT/HIGHLY
AMPLIFIED POLAR TROUGH DOMINATES THE FLOW ACROSS THE EASTERN
USA/WESTERN ATLANTIC TO THE GULF OF MEXICO/WESTERN CARIBBEAN. THE
TROUGH IS TO BRIEFLY PULL DURING THE DAY ON FRIDAY...BUT UNDER
INFLUENCE OF A SECOND PERTURBATION IT IS TO STRENGTHEN ONCE AGAIN
THROUGH SATURDAY MORNING. AS IT MEANDERS OVER THE GULF-WESTERN
ATLANTIC A SUBTROPICAL JET MAXIMA IS FORECAST TO GRADUALLY ROUND
THE BASE OF THE LONG WAVE AXIS...TO THEN SLOWLY PULL ACROSS THE
BAHAMAS-NORTH OF THE ISLANDS. THIS IS TO GENERALLY FAVOR A NEUTRAL
TO WEAK CONVERGENT PATTERN AS IT RELOCATES NORTH OF THE ISLANDS.

AT LOW LEVELS...THE POLAR TROUGH SUSTAINS A MEANDERING FRONT
ACROSS THE TURKS/SOUTHEAST BAHAMAS-EASTERN CUBA TO THE WESTERN
CARIBBEAN. A POLAR RIDGE OVER THE GULF...MEANWHILE...SUSTAINS
FAIRLY STRONG NORTHERLY WINDS ACROSS THE WESTERN-CENTRAL
CARIBBEAN...WITH WINDS ACROSS SOUTHERN CENTRAL AMERICA PEAKING
AROUND 30-35KT. THIS ALSO FAVORS A PREFRONTAL SHEAR LINE ACROSS
HISPANIOLA TO THE SOUTHERN CARIBBEAN...WITH ENVIRONMENTAL
CONDITIONS FAVORING AN ECHO TRAINING SITUATION ACROSS NORTHERN
PORTIONS OF HISPANIOLA. THROUGH FRIDAY EVENING THE SURFACE FRONT
RETROGRESSES ACROSS THE CENTRAL BAHAMAS-CUBA...WHERE IT IS TO THEN
FRONTOLIZE. LIKEWISE...SHEAR LINE CONFLUENCE IS ALSO FORECAST TO
WEAKEN. MEANWHILE...THE FRONT-SHEAR LINE...AS IT MEANDERS ACROSS
HISPANIOLA-EASTERN CUBA/THE TURKS IS TO SUSTAIN SCATTERED
CONVECTION. IN THIS AREA EXPECTING RAINFALL AMOUNTS OF 15-30MM/DAY
AND MAXIMA OF 40-80MM THROUGH FRIDAY MORNING. ON FRIDAY TO
SATURDAY EXPECTING RAINFALL AMOUNTS OF 05-10MM/DAY AND MAXIMA OF
15-25MM. ACROSS JAMAICA...THIS IS TO RESULT IN RAINFALL AMOUNTS OF
10-15MM/DAY AND MAXIMA OF 20-45MM... WHILE OVER COSTA
RICA/SOUTHERN NICARAGUA THE SHEAR LINE WILL FAVOR RAINFALL AMOUNTS
OF 10-15MM/DAY AND MAXIMA OF 20-40MM. OVER NORTHERN HONDURAS...THE
LOW LEVEL NORTHERLIES WILL RESULT IN RAINFALL AMOUNTS OF
10-15MM/DAY AND MAXIMA OF 20-30MM.

NEXT POLAR FRONT SURGES ACROSS THE SOUTHEAST USA THROUGH FRIDAY
EVENING. EARLY ON SATURDAY MORNING IT WILL PUSH ACROSS CENTRAL
FLORIDA TO THE NORTHERN GULF...MOVING TO THE NORTHWEST
BAHAMAS-STRAITS OF FLORIDA LATER ON SATURDAY. THROUGH SUNDAY
MORNING IT IS TO MEANDER INTO THE CENTRAL BAHAMAS. 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-CENTRAL CARIBBEAN...INTO THE MONA PASSAGE/WESTERN
PUERTO RICO ON SUNDAY EVENING. OVER THE SOUTHEAST BAHAMAS-TURKS
AND EASTERN CUBA...THE SHEAR LINE WILL SUSTAIN RAINFALL AMOUNTS OF
10-15MM/DAY AND MAXIMA OF 20-35MM. STRONG NORTHERLIES ACROSS THE
WESTERN CARIBBEAN ARE TO 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. ACROSS NORTHERN HISPANIOLA THE SHEAR LINE WILL SUSTAIN
RAINFALL AMOUNTS OF 10-15MM/DAY AND MAXIMA OF 20-35MM... WHILE
OVER PUERTO RICO EXPECTING RAINFALL AMOUNTS OF 05-10MM/DAY AND
MAXIMA OF 15-25MM.

THE SURGING LOW LEVEL NORTHERLIES OVER SOUTHERN CENTRAL AMERICA TO
THE EASTERN PACIFIC WILL SUSTAIN THE SOUTHWARD DISPLACEMENT OF THE
ITCZ TO THE CAUCA VALLEY IN SOUTHERN COLOMBIA/NORTHERN ECUADOR.
THIS WILL ENHANCE LOW LEVEL CONVERGENCE TO RESULT IN RAINFALL
AMOUNTS OF 15-30MM/DAY AND MAXIMA OF 40-80MM THROUGH FRIDAY
MORNING...AND 05-10MM/DAY AND MAXIMA OF 15MM/DAY ON FRIDAY TO
SATURDAY. ON THE ANDEAN REGION/WESTERN COASTAL PLAINS OF
COLOMBIA...UPWELLING OF COLD WATER WILL LEAD TO A MORE STABLE
ATMOSPHERE AND A DECREASE IN CONVECTION. EARLY IN THE CYCLE EXPECT
RAINFALL AMOUNTS OF 00-05MM/DAY AND MAXIMA OF 10MM...BUT THIS
QUICKLY DECREASES IN INTENSITY/AREA COVERAGE.

THE WESTERN ATLANTIC TROUGH IS TO PRESS AGAINST A RIDGE TO THE
EAST...AS THE LATTER IS TO ENVELOP THE CENTRAL-EASTERN ATLANTIC
WHILE ANCHORING ON A 500 HPA HIGH NEAR 30N 35W. THE PERSISTENT MID
LEVEL RIDGE IS TO SUSTAIN A TRADE WINDS CAP ACROSS THE EASTERN
CARIBBEAN/NORTHERN SOUTH AMERICA. EROSION OF THIS
INVERSION...HOWEVER...IS EXPECTED THROUGH SUNDAY MORNING AS POLAR
TROUGH PRESSES TO THE EAST AND THE RIDGE WEAKENS. THIS WILL ALLOW
FOR DEEPER MOISTURE TO POOL ACROSS HISPANIOLA-PUERTO RICO IN
ASSOCIATION WITH LOW LEVEL SHEAR LINE ENTERING THE FORECAST AREA.

AN ELONGATED TUTT BOUNDS THE EASTERN-SOUTHERN FRINGES OF THIS
RIDGE...WITH AXIS TO THE WEST-SOUTHWEST FROM WESTERN
AFRICA...ALONG 25N 35W TO JUST NORTH OF THE GUIANAS. UNDER
INFLUENCE OF THE RIDGE TO THE NORTH THE TUTT IS TO STRETCH FARTHER
WEST ACROSS THE SOUTHERN WINDWARD ISLES TO NORTHERN VENEZUELA. BUT
THIS WILL NOT BE DEEP/STRONG ENOUGH TO OVERCOME NEGATIVE INFLUENCE
OF THE MID LEVEL RIDGE/TRADE WINDS INVERSION. ENHANCEMENT...IF
ANY...WILL LIMIT TO EQUATORIAL SOUTH AMERICA-SOUTHERN GUIANAS. IN
THIS AREA EXPECTING RAINFALL AMOUNTS OF 05-10MM/DAY AND MAXIMA OF
15-20MM.

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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