Tropical Weather Discussion
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000
AXNT20 KNHC 252342
TWDAT

TROPICAL WEATHER DISCUSSION...CORRECTED
NWS NATIONAL HURRICANE CENTER MIAMI FL
705 PM EST THU DEC 25 2014

TROPICAL WEATHER DISCUSSION FOR NORTH AMERICA...CENTRAL
AMERICA...GULF OF MEXICO...CARIBBEAN SEA...NORTHERN SECTIONS OF
SOUTH AMERICA...AND ATLANTIC OCEAN TO THE AFRICAN COAST FROM THE
EQUATOR TO 32N. THE FOLLOWING INFORMATION IS BASED ON SATELLITE
IMAGERY...WEATHER OBSERVATIONS...RADAR...AND METEOROLOGICAL
ANALYSIS.

BASED ON 1800 UTC SURFACE ANALYSIS AND SATELLITE IMAGERY THROUGH
2330 UTC.

...SPECIAL FEATURES...

STRONG HIGH PRES BEHIND THE COLD FRONT MOVING ACROSS THE W
CARIBBEAN WILL DRIVE INCREASING WINDS ALONG THE COAST OF
COLOMBIA WHICH WILL REACH GALE FORCE TONIGHT THROUGH FRI
MORNING. SEAS ARE EXPECTED TO BE FROM 10-12 FEET ACROSS THIS
AREA. PLEASE REFER TO THE HIGH SEAS FORECAST...MIAHSFAT2/FZNT02
KNHC...AND THE OFFSHORE FORECAST...MIAOFFNT3/FZNT23 KNHC...FOR
MORE DETAILS.

...THE ITCZ/THE MONSOON TROUGH...

THE MONSOON TROUGH REMAINS ACROSS AFRICA. THE ITCZ EXTENDS FROM
05N09W TO 05N26W TO 04N40W TO 07N49W. ISOLATED MODERATE
CONVECTION IS ALONG THE ITCZ BETWEEN 24W-28W AND 37W-48W.

...DISCUSSION...

GULF OF MEXICO...

HIGH PRESSURE PREVAILS ACROSS THE BASIN AFTER THE FRONTAL
PASSAGE. WITH THIS...A GENTLE TO MODERATE ANTICYCLONIC FLOW IS
OBSERVED ACROSS THE BASIN. UPPER-LEVEL SW FLOW IS BRINGING
PLENTY OF MOISTURE TO THE GULF FROM THE EPAC AND W CARIBBEAN.
ISOLATED CONVECTION IS N OF 25N AND W OF 90W. FAIR WEATHER
PREVAILS ELSEWHERE. LOOKING AHEAD OVER THE NEXT 24-48
HOURS...EXPECT FOR THE NEXT COLD FRONT TO APPROACH THE TEXAS
COAST BY SAT AND THEN SLOWLY MOVING INTO THE NW GULF.

CARIBBEAN SEA...

FRESH TO STRONG TRADEWINDS PREVAIL ACROSS THE EAST AND CENTRAL
CARIBBEAN WITH THE STRONGEST WINDS OF 25-30 KT NEAR THE COAST OF
COLOMBIA. THE LATEST SCATTEROMETER DATA ONCE AGAIN CONFIRMED THE
PRESENCE OF THESE WIND SPEEDS. SEE THE SPECIAL FEATURES ABOVE
FOR MORE INFORMATION. A COLD FRONT IS MOVING ACROSS THE WESTERN
CARIBBEAN ALONG 22N81W TO 16N86W. GENTLE TO MODERATE NORTHERLY
WINDS ARE BLOWING ACROSS THE NW CARIBBEAN BEHIND OF A COLD FRONT
WITH ISOLATED SHOWERS ALONG THE BOUNDARY. SHALLOW MOISTURE
EMBEDDED IN THE TRADE WIND FLOW CONTINUES TO MOVE ACROSS THE
REGION PRODUCING ISOLATED PASSING SHOWERS AFFECTING THE LESSER
ANTILLES AND PUERTO RICO AS DEPICTED BY THE SAN JUAN DOPPLER
RADAR. GENTLE TRADEWINDS PREVAIL ELSEWHERE WITH FAIR WEATHER DUE
TO STRONG SUBSIDENCE. EXPECT FOR THE COLD FRONT TO STALL FROM
WESTERN CUBA TO THE GULF OF HONDURAS AND GRADUALLY DISSIPATE
THROUGH FRI. FRESH NORTHERLY WINDS ARE EXPECTED IN THE WAKE OF
THE FRONT. MODEL GUIDANCE SUGGESTS THAT A WEAKENING FRONTAL
BOUNDARY WILL REACH THE GREATER ANTILLES ON SUNDAY WITH A BAND
OF MOISTURE EXTENDING ACROSS PUERTO RICO...HISPANIOLA AND
EASTERN CUBA.

HISPANIOLA...

A DRY AIR MASS CONTINUES ACROSS THE ISLAND SUPPORTING FAIR
WEATHER. SHALLOW MOISTURE EMBEDDED IN THE TRADE WIND FLOW
CONTINUES TO MOVE ACROSS THE REGION PRODUCING WEAK...ISOLATED
PASSING SHOWERS. A WEAKENING FRONTAL BOUNDARY WILL BRING SOME
INCREASE IN MOISTURE AND POSSIBLY ENHANCING CONVECTION BY SUNDAY.

ATLANTIC OCEAN...

THE STRONG COLD FRONT CONTINUES TO MOVE E ACROSS THE SW PORTION
OF THE BASIN...EXTENDING FROM 44N64W TO WESTERN CUBA NEAR 23N80W
THEN S ACROSS THE W CARIBBEAN. SCATTERED MODERATE CONVECTION
REMAINS N OF 30N BETWEEN 55W-68W. A 1023 MB HIGH IS E OF THE
FRONT CENTERED NEAR 32N59W AND EXTENDING A RIDGE ACROSS THE
CENTRAL ATLANTIC AND THE NORTHERN PORTION OF THE CARIBBEAN SEA.
MODERATE TO LOCALLY FRESH EASTERLY WINDS ARE NOTED ACROSS THE
SOUTHERN PERIPHERY OF THE RIDGE. TO THE E...ANOTHER COLD FRONT
IS PRODUCING SCATTERED MODERATE CONVECTION N OF 21N BETWEEN 24W-
46W. THIS BOUNDARY EXTENDS FROM 45N32W TO 19N42W. THE PRESSURE
GRADIENT BETWEEN THE LOW PRES AND THE RIDGE TO THE W IS
RESULTING IN AN AREA OF FRESH TO STRONG NORTHERLY WINDS OVER THE
CENTRAL ATLANTIC...ESPECIALLY N OF 28N BETWEEN 44W-53W. A 1037
MB SURFACE HIGH DOMINATES THE E ATLANTIC. AT UPPER LEVELS...A
RIDGE/TROUGH/RIDGE PATTERN IS OBSERVED ACROSS THE REGION. EXPECT
FOR THE COLD FRONT ACROSS THE W ATLANTIC TO WEAKEN AND STALL
ENHANCING CONVECTION ACROSS THE CENTRAL ATLANTIC AND CARIBBEAN
WHILE THE FRONT ACROSS THE E ATLANTIC WILL CONTINUE MOVING E
WITH CONVECTION.


FOR ADDITIONAL INFORMATION PLEASE VISIT
HTTP://WWW.HURRICANES.GOV/MARINE

$$
ERA



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