000
AXNT20 KNHC 130606
TWDAT 

TROPICAL WEATHER DISCUSSION
NWS TPC/NATIONAL HURRICANE CENTER MIAMI FL
205 AM EDT WED MAY 13 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 0000 UTC SURFACE ANALYSIS AND SATELLITE IMAGERY
THROUGH 0545 UTC.

...THE ITCZ...

FROM 8N9W TO THE EQUATOR ALONG 19W...TO 2S23W 3S30W 3S36W AND
INTO NORTHEASTERN BRAZIL NEAR 5S42W. ISOLATED MODERATE SHOWERS
TO LOCALLY STRONG THUNDERSTORMS ARE FROM THE EQUATOR TO 6N
BETWEEN 9W AND 46W. A SURFACE TROUGH IS ALONG 15W/16W FROM
5N TO 15N WITH NO SIGNIFICANT DEEP CONVECTIVE PRECIPITATION.

...DISCUSSION...

THE GULF OF MEXICO...
AN UPPER LEVEL RIDGE IS ALONG 100W FROM 14N IN THE EASTERN 
PACIFIC OCEAN TO 30N IN SOUTH CENTRAL TEXAS. THE ANTICYCLONIC 
FLOW AROUND THE 100W RIDGE REACHES TO AT LEAST 90W. THE MIDDLE 
LEVEL TO UPPER LEVEL FLOW THAT IS TO THE EAST OF 90W IS 
NORTHWESTERLY...RELATED TO A TROUGH FROM CUBA TO THE BAHAMA
ISLANDS. WEAK SOUTHEASTERLY RETURN FLOW COVERS THE AREA.
BROAD SURFACE LOW PRESSURE EXTENDS FROM JUST WEST OF THE ISTHMUS 
OF TEHUANTEPEC TO CENTRAL MEXICO TO THE TEXAS BIG BEND. SHOWERS
AND THUNDERSTORMS ARE IN MEXICO FROM 22N TO 27N BETWEEN 101W
AND 104W.

THE CARIBBEAN SEA...
MIDDLE LEVEL TO UPPER LEVEL NORTHWESTERLY WIND FLOW MOVES FROM 
THE GULF OF MEXICO TO THE EAST OF 90W...INTO THE NORTHWESTERN 
CARIBBEAN SEA. THIS FLOW REGIME MEETS A SEPARATE AREA OF BROAD 
UPPER LEVEL FLOW ALONG THE LINE FROM THE SOUTHERN BORDER OF 
HAITI AND THE DOMINICAN REPUBLIC TO 15N79W TO NORTHERN NICARAGUA.
A MIDDLE LEVEL TO UPPER LEVEL TROUGH SPANS THE AREA FROM CUBA TO 
THE BAHAMA ISLANDS. STRONG SHOWERS AND THUNDERSTORMS ARE IN 
NORTHERN COLOMBIA FROM 5N TO 9N BETWEEN 74W AND 77W...IN AN AREA
OF BROAD SURFACE LOW PRESSURE AND THE POSSIBLE PRESENCE OF THE 
ITCZ. A SURFACE TROUGH IS ALONG THE LINE FROM 21N67W TO CENTRAL 
PUERTO RICO TO 14N65W. SHOWERS ARE POSSIBLE FROM 15N TO 21N
BETWEEN 60W AND 70W.

THE ATLANTIC OCEAN...
A MIDDLE TO UPPER LEVEL TROUGH IS MOVING AWAY FROM THE U.S.A.
EAST COAST TO THE NORTH OF 32N/33N. A REMNANT MIDDLE TO UPPER 
LEVEL TROUGH THAT MOST PROBABLY CAME BEFORE THE 32N/33N FEATURE
SUPPORTS THE COLD FRONT THAT STRETCHES FROM BERMUDA TO 30N71W...
AND THE STATIONARY FRONT THAT CONTINUES FROM 30N71W TO 30N78W TO 
FLORIDA NEAR 27N82W. ANOTHER PART OF A STATIONARY FRONT IS ALONG 
THE LINE FROM FLORIDA NEAR 29N82W BEYOND 32N89W. A MIDDLE LEVEL 
TO UPPER LEVEL TROUGH SPANS THE AREA FROM CUBA TO THE BAHAMA 
ISLANDS...RELATED TO THE STATIONARY FRONT. SHOWERS ARE POSSIBLE
FROM 24N TO 32N BETWEEN 70W AND 81W...OVER THE ATLANTIC WATERS
AND PARTS OF FLORIDA. A MIDDLE LEVEL TO UPPER LEVEL CYCLONIC 
CIRCULATION CENTER IS NEAR 22N45W. CYCLONIC FLOW EXISTS FROM
12N TO 30N BETWEEN 35W AND 61W.

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