000
AXNT20 KNHC 092351
TWDAT 

TROPICAL WEATHER DISCUSSION 
NWS TPC/NATIONAL HURRICANE CENTER MIAMI FL
805 PM EDT THU APR 09 2009

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...METEOROLOGICAL ANALYSIS...WEATHER
OBSERVATIONS...AND RADAR.

BASED ON 1800 UTC SURFACE ANALYSIS AND SATELLITE IMAGERY
THROUGH 2315 UTC.

...THE ITCZ...
FROM SOUTHERN LIBERIA NEAR 4N8W...CROSSING THE EQUATOR ALONG 
18W...TO 1S20W TO 4S30W INTO NORTHEASTERN BRAZIL NEAR 4S39W.
WARMING CLOUD TOP TEMPERATURES AND DISSIPATING PRECIPITATION
ARE SOUTH OF 4N TO THE EAST OF 14W...TO THE SOUTH OF 3N
BETWEEN 20W AND 23W.

...DISCUSSION...

THE GULF OF MEXICO...
MIDDLE LEVEL TO UPPER LEVEL WESTERLY FLOW COVERS THE AREA.
A CYCLONIC SYSTEM IS DEVELOPING IN THE CENTRAL U.S.A.
A DEEP LAYER TROUGH IS COMPLETE WITH A SURFACE FRONTAL 
SYSTEM...EXTENDING FROM KANSAS TO OKLAHOMA TO TEXAS MOVING 
EASTWARD. HIGH CLOUDS ARE COVERING MOST OF THE AREA TO THE
NORTH OF 20N FROM WEST TO EAST. A SURFACE RIDGE PASSES OVER
THE NORTHERN BAHAMAS TO SOUTH FLORIDA INTO THE CENTRAL AND
WEST CENTRAL GULF OF MEXICO.

THE CARIBBEAN SEA...
MIDDLE LEVEL WESTERLY FLOW MOVES FROM THE WESTERN HALF OF
THE AREA. THIS WESTERLY FLOW MIXES WITH LARGE-SCALE UPPER
LEVEL SOUTHWESTERLY FLOW THAT IS MOVING FROM THE EASTERN
PACIFIC OCEAN ACROSS SOUTHERN NICARAGUA AND COSTA RICA...
AND UPPER LEVEL SOUTHERLY FLOW THAT MOVES FROM SOUTH AMERICA
AND CURVES ANTICYCLONICALLY ACROSS AND BEYOND THE EASTERN
CARIBBEAN SEA. LOW LEVEL CYCLONIC FLOW CONTINUES. A SURFACE
TROUGH IS ALONG 64W/65W SOUTH OF 18N. BROKEN TO OVERCAST 
MULTILAYERED CLOUDS AND POSSIBLE PRECIPITATION ARE FROM 
13N TO 18N BETWEEN 60W AND 68W...FROM 18N TO 19N BETWEEN
64W AND 67W...AND IN CENTRAL HISPANIOLA AND IN JAMAICA. 

THE ATLANTIC OCEAN...
A COLD FRONT PASSES THROUGH 31N58W TO 27N60W TO 26N62W.
A STATIONARY FRONT CONTINUES FROM 26N62W TO 23N66W TO NORTHERN 
HAITI NEAR 20N72W. LOW LEVEL ANTICYCLONIC FLOW MOVES AROUND
A 1022 MB HIGH PRESSURE CENTER NEAR 26N73W. A SECOND RIDGE IS TO 
THE EAST OF THE COLD FRONT...FROM 22N60W TO 28N52W BEYOND 32N45W.
A BROAD AREA OF CYCLONIC FLOW IS IN THE ATLANTIC OCEAN TO THE 
WEST OF 52W. A FEW COLD FRONTS THAT ARE TO THE NORTH OF 32N ARE
MOVING THROUGH THIS TROUGH. AN UPPER LEVEL RIDGE IS ALONG 10N54W 
TO 24N53W BEYOND 32N52W. A LARGE-SCALE MIDDLE LEVEL TO UPPER 
LEVEL TROUGH IS ALONG 24N33W 17N38W 11N40W. UPPER LEVEL 
SOUTHERLY WIND FLOW MOVES FROM THE ATLANTIC OCEAN TO THE 
SOUTHWEST OF THE CAPE VERDE ISLANDS NORTHEASTWARD AND IT MEETS
A MIDDLE LEVEL TO UPPER LEVEL CYCLONIC CIRCULATION CENTER THAT 
IS DROPPING SOUTHWARD RIGHT ON TOP OF THE CANARY ISLANDS.

$$
MT