000
AXNT20 KNHC 172328
TWDAT 

TROPICAL WEATHER DISCUSSION
NWS NATIONAL HURRICANE CENTER MIAMI FL  
805 PM EDT THU MAR 17 2011

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

BASED ON 1800 UTC SURFACE ANALYSIS AND SATELLITE IMAGERY
THROUGH 2245 UTC.

...THE ITCZ...

FROM THE SOUTHERN COAST OF LIBERIA...CROSSING THE EQUATOR ALONG
19W...TO 1S22W...FROM 1S TO THE EQUATOR BETWEEN 22W AND 40W...
INTO NORTHEASTERN BRAZIL NEAR 1S45W. NUMEROUS STRONG RAINSHOWERS 
AND THUNDERSTORMS ARE WITHIN 30 NM TO 60 NM ON EITHER SIDE OF
THE LINE THAT CURVES FROM 1S16W TO 2N17W TO 3N19W TO 2N21W.
SCATTERED MODERATE TO STRONG RAINSHOWERS AND THUNDERSTORMS ARE
FROM THE EQUATOR TO 2N BETWEEN 32W AND 42W.

...DISCUSSION...

THE GULF OF MEXICO AND THE ATLANTIC OCEAN TO THE WEST OF 70W...
MIDDLE LEVEL TO UPPER LEVEL ANTICYCLONIC FLOW COVERS THE 
NORTHWESTERN CORNER OF THE GULF OF MEXICO. MIDDLE LEVEL TO 
UPPER LEVEL SOUTHWESTERLY WIND FLOW COVERS THE SOUTHWESTERN 
CORNER OF THE AREA. THESE TWO FLOW REGIMES MERGE NEAR THE
CENTRAL GULF OF MEXICO AND WESTERLY WIND FLOW COVERS THE
REST OF THE AREA THAT IS TO THE EAST OF 90W. UPPER LEVEL
NORTHWESTERLY WIND FLOW MOVES THROUGH ALABAMA AND GEORGIA ACROSS
FLORIDA...TOWARD THE BAHAMAS AND THE WESTERN ATLANTIC OCEAN.
THIS FLOW IS IN RESPONSE TO THE UPPER LEVEL TROUGH THAT SUPPORTS
THE WESTERN ATLANTIC OCEAN COLD FRONT THAT PASSES THROUGH 32N70W
TO 29N74W TO 28N80W. A SURFACE TROUGH ALSO GOES FROM ANDROS
ISLAND IN THE BAHAMAS TO 28N75W. RAINSHOWERS ARE POSSIBLE WITHIN
15 NM TO 30 NM ON EITHER SIDE OF THE TROUGH. A SURFACE RIDGE
PASSES THROUGH THE FLORIDA PANHANDLE TOWARD THE MEXICO GULF
COAST NEAR 20N97W IN THE SOUTHWESTERN CORNER OF THE GULF OF
MEXICO.

THE CARIBBEAN SEA...
BROKEN LOW LEVEL TO MIDDLE LEVEL CLOUDS AND POSSIBLE RAINSHOWERS 
ARE FROM HISPANIOLA TO 23N BETWEEN 69W AND 76W IN THE ATLANTIC
OCEAN. THIS ARE OF CLOUDS AND PRECIPITATION COVERS THE WATERS 
THAT ARE TO THE NORTH OF HISPANIOLA AND CUBA...AND THE SOUTHERN 
BAHAMAS. BROKEN LOW LEVEL TO MIDDLE LEVEL CLOUDS AND POSSIBLE 
RAINSHOWERS ARE FROM THE COASTS OF COLOMBIA AND VENEZUELA TO 16N
BETWEEN 63W AND 74W...AND FROM 15N TO HAITI BETWEEN 72W AND 77W.
SIMILAR CLOUDS AND POSSIBLE PRECIPITATION COVER THE AREAS FROM 
NORTHERN NICARAGUA TO THE YUCATAN PENINSULA AND 20N BETWEEN 83W 
AND 93W. 
 
THE REST OF THE ATLANTIC OCEAN...
A DEEP LAYER TROUGH PASSES THROUGH 32N33W TO 27N37W TO 20N43W.
THIS TROUGH SUPPORTS THE COLD FRONT THAT PASSES THROUGH 32N32W
TO 26N36W TO 24N41W. A DISSIPATING COLD FRONT CONTINUES FROM 
24N41W TO 25N60W. MODERATE RAINSHOWERS ARE WITHIN 60 NM TO 90 NM 
ON EITHER SIDE OF THE LINE THAT PASSES THROUGH 32N30W TO 28N32W 
TO 25N36W. RAINSHOWERS ARE POSSIBLE WITHIN 60 NM TO 90 NM ON
EITHER SIDE OF THE REST OF THE FRONTAL BOUNDARY. A SURFACE TROUGH
IS ALONG 26N34W 23N35W 19N36W. RAINSHOWERS ARE POSSIBLE WITHIN 
60 NM ON EITHER SIDE OF 23N34W 13N35W. A SECOND SURFACE TROUGH 
CURVES FROM 22N51W TO 15N50W. RAINSHOWERS ARE POSSIBLE FROM 14N 
TO 23N BETWEEN 42W AND 52W...AND FROM 15N TO 23N BETWEEN 56W AND 
59W. BROAD SURFACE ANTICYCLONIC FLOW IS TO THE NORTH OF THE 
FRONT BETWEEN 40W AND 60W. A SURFACE RIDGE IS TO THE EAST OF THE 
FRONT...PASSING THROUGH 33N18W TO 24N29W. BROKEN LOW LEVEL TO 
MIDDLE LEVEL CLOUDS AND POSSIBLE RAINSHOWERS ARE FROM 21N TO 27N 
BETWEEN 63W AND 67W...AND FROM HISPANIOLA TO 23N BETWEEN 69W AND 
76W. THE SECOND AREA OF CLOUDS AND PRECIPITATION COVERS THE 
WATERS THAT ARE TO THE NORTH OF HISPANIOLA AND CUBA...AND THE 
SOUTHERN BAHAMAS. 

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

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MT