000
AXNT20 KNHC 221720
TWDAT 

TROPICAL WEATHER DISCUSSION
NWS TPC/NATIONAL HURRICANE CENTER MIAMI FL
205 PM EDT TUE SEP 22 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 1200 UTC SURFACE ANALYSIS AND SATELLITE IMAGERY
THROUGH 1645 UTC.

...TROPICAL WAVES...

AN ATLANTIC OCEAN TROPICAL WAVE GOES FROM 17N36W TO A 1013 MB
LOW PRESSURE CENTER NEAR 15N39W...TO 10N41W 7N42W...MOVING WEST
15 KT. ISOLATED MODERATE SHOWERS FROM 7N TO 8N BETWEEN 42W AND 
43W.   

...THE ITCZ...

12N16W 8N30W 10N39W 7N50W 7N58W IN NORTHERN GUYANA. SCATTERED 
MODERATE SHOWERS TO ISOLATED STRONG THUNDERSTORMS FROM 9N TO 11N 
BETWEEN THE COAST OF AFRICA AND 18W. ISOLATED MODERATE SHOWERS 
ARE WITHIN 60 NM ON EITHER SIDE OF 7N17W 7N25W 7N29W 6N37W 6N50W 
9N60W.

...DISCUSSION...

THE GULF OF MEXICO...
AN UPPER LEVEL RIDGE EXTENDS FROM SOUTH CENTRAL COASTAL LOUISIANA
TO THE MEXICO COAST NEAR 23N98W. AN UPPER LEVEL TROUGH IS 
APPROACHING FROM THE NORTHWEST...STILL MOVING THROUGH TEXAS AT 
THIS TIME. A SURFACE TROUGH IS ABOUT 150 NM TO THE SOUTHEAST OF 
THE COLD FRONT THAT THE TROUGH SUPPORTS. THE TROUGH IS ALONG THE
TEXAS COASTAL PLAINS. SHOWERS AND THUNDERSTORMS HAVE DEVELOPED 
IN THE TEXAS COASTAL PLAINS FROM THE UPPER COAST TO THE MIDDLE 
COAST. A WEAK UPPER LEVEL TROUGH EXTENDS FROM JUST TO THE NORTH
OF THE YUCATAN CHANNEL TOWARD THE NORTHWESTERN CORNER OF THE 
YUCATAN PENINSULA TO THE ISTHMUS OF TEHUANTEPEC. SHOWERS FROM 
19N TO 21N BETWEEN 94W AND 96W. ISOLATED MODERATE SHOWERS ARE
TO THE SOUTH OF 26N TO THE EAST OF 90W. A SEPARATE UPPER LEVEL 
TROUGH IS MOVING FROM ALABAMA TOWARD GEORGIA...PASSING THROUGH 
THE FLORIDA BIG BEND INTO THE NORTHEASTERN GULF OF MEXICO NEAR 
28N86W. ISOLATED MODERATE SHOWERS COVER THE AREA FROM 27N TO 31N
BETWEEN 85W AND 90W. 

THE CARIBBEAN SEA...
THE SOUTHERN END OF AN UPPER LEVEL TROUGH REACHES 12N63W. 
CYCLONIC FLOW COVERS THE AREA TO THE EAST OF 70W. ISOLATED 
MODERATE SHOWERS TO POSSIBLE THUNDERSTORMS COVER THE AREA
FROM 17N TO 23N BETWEEN 53W AND 67W. ISOLATED MODERATE SHOWERS 
COVER THE AREA FROM 16N TO COASTAL CUBA BETWEEN HAITI AND THE 
YUCATAN PENINSULA...IN AN AREA THAT IS TO THE SOUTH OF CYCLONIC 
FLOW THAT IS TO THE EAST OF FLORIDA IN THE ATLANTIC OCEAN...AND
TO THE SOUTHEAST OF THE TROUGH THAT RUNS FROM THE YUCATAN 
CHANNEL SOUTHWESTWARD...AND DISSIPATING UPPER LEVEL CYCLONIC
FLOW THAT IS ABOUT 120 NM TO THE SOUTH OF JAMAICA. STRONG 
SHOWERS AND THUNDERSTORMS SURROUND THE ITCZ IN THE EASTERN 
PACIFIC OCEAN...TO THE SOUTH OF 10N FROM COASTAL COLOMBIA TO 
BOTH SIDES OF PANAMA AND WESTWARD.

THE ATLANTIC OCEAN...
AN UPPER LEVEL TROUGH IS ALONG 78W/79W FROM 31N TO GRAND BAHAMA 
ISLAND TO THE COAST OF CUBA NEAR 21N77W. THE 1017 MB LOW 
PRESSURE CENTER NEAR 31N THAT IS ALONG THE TROUGH IS THE REMNANT 
LOW OF HURRICANE FRED. SHOWERS AND POSSIBLE THUNDERSTORMS ARE 
FROM 29N BEYOND 32N BETWEEN 77W AND 80W...FROM 26N TO 29N 
BETWEEN 74W AND 76W...AND FROM THE SOUTHERN BAHAMAS AND CUBA
TO 23N BETWEEN GREAT INAGUA AND 80W. AN UPPER LEVEL TROUGH 
PASSES JUST TO THE EAST OF BERMUDA TO 26N64W TO 17N63W INTO
THE SOUTHEASTERN CARIBBEAN SEA NEAR 12N63W. SCATTERED MODERATE 
SHOWERS TO ISOLATED STRONG THUNDERSTORMS ARE FROM 25N BEYOND 32N 
BETWEEN 58W AND 72W. ISOLATED MODERATE SHOWERS TO POSSIBLE 
THUNDERSTORMS COVER THE AREA FROM 17N TO 23N BETWEEN 53W AND 67W.
A SURFACE TROUGH IS ALONG 24N45W 20N47W...TO A 1011 MB LOW 
PRESSURE CENTER NEAR 16N48W TO 11N49W. THUNDERSTORMS IN SOME
CELLS FROM 18N TO 20N BETWEEN 43W AND 46W. POSSIBLE SHOWERS ARE
ELSEWHERE FROM 14N TO 21N BETWEEN 40W AND 48W. AN UPPER LEVEL 
TROUGH EXTENDS FROM ONE CYCLONIC CIRCULATION CENTER
FROM 33N25W TO 27N23W TO 22N22W.

$$
MT