000
AXNT20 KNHC 251725
TWDAT 

TROPICAL WEATHER DISCUSSION
NWS TPC/NATIONAL HURRICANE CENTER MIAMI FL
205 PM EDT MON MAY 25 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...
A TROPICAL WAVE IS ALONG 60W/61W TO THE SOUTH 10N MOVING 
WESTWARD 15 KT. THE WAVE IS MARKED BY A SMALL AMOUNT OF
CYCLONIC FLOW ON VISIBLE SATELLITE IMAGERY. NO SIGNIFICANT
DEEP CONVECTIVE PRECIPITATION ACCOMPANIES THIS WAVE.

AN ATLANTIC OCEAN TROPICAL WAVE IS ALONG 25W/26W TO THE SOUTH
OF 11N...ITS FIRST TIME ON THE SURFACE MAP. THE WAVE IS MARKED 
BY A SMALL AMOUNT OF CYCLONIC FLOW ON VISIBLE SATELLITE IMAGERY. 
NO SIGNIFICANT DEEP CONVECTIVE PRECIPITATION ACCOMPANIES THIS 
WAVE. 

...THE ITCZ...
FROM LIBERIA NEAR 7N10W TO 3N20W...CROSSING THE EQUATOR NEAR 
30W...INTO NORTHEASTERN BRAZIL NEAR 3S48W. ISOLATED AND 
DISORGANIZED MODERATE SHOWERS ARE TO THE SOUTH OF 6N TO THE
EAST OF 20W. SCATTERED MODERATE SHOWERS TO ISOLATED STRONG
THUNDERSTORMS ARE TO THE SOUTH OF 2N BETWEEN 39W AND 47W.

...DISCUSSION...

FROM THE GULF OF MEXICO TO CUBA AND THE BAHAMA ISLANDS...
BROAD MIDDLE LEVEL TO UPPER LEVEL CYCLONIC FLOW IS ALONG 
A LINE FROM SOUTHEASTERN LOUISIANA TO SOUTH FLORIDA TO THE 
BAHAMA ISLANDS NEAR CROOKED ISLAND AND THE ACKLINS. SHOWERS
AND THUNDERSTORMS IN THE ATLANTIC OCEAN ARE ASSOCIATED WITH
A SURFACE TROUGH THAT IS ALONG THE LINE FROM GREAT INAGUA TO 
ELEUTHERA ISLAND. SHOWERS AND THUNDERSTORMS FROM 27N TO 30N 
BETWEEN 90W AND 94W ARE ASSOCIATED WITH A SHORTWAVE TROUGH
THAT IS MOVING ALONG THE COAST OF SOUTH CENTRAL LOUISIANA...
EXTENDING ABOUT 150 NM TO THE SOUTH INTO THE GULF WATERS.
  
THE CARIBBEAN SEA...
WATER VAPOR SATELLITE IMAGERY AND CIMSS SATELLITE DERIVED WINDS
FROM 25/1500 UTC SHOW A MIDDLE LEVEL TO UPPER LEVEL RIDGE FROM 
CENTRAL AMERICA INTO THE NORTHWESTERN CORNER OF THE AREA.
THE NORTHWESTERLY FLOW ON THE EASTERN SIDE OF THE RIDGE COVERS 
THE ENTIRE AREA. EARLIER SHOWER AND THUNDERSTORM ACTIVITY APPEARS
TO BE WEAKENING FROM 16N TO 19N BETWEEN 74W AND 78W IN AN AREA 
OF UPPER LEVEL DIFFLUENT WIND FLOW.

THE ATLANTIC OCEAN...
A SURFACE TROUGH SPANS THE BAHAMA ISLANDS ALONG THE LINE FROM 
GREAT INAGUA TO ELEUTHERA ISLAND. SHOWERS AND THUNDERSTORMS ARE 
WITHIN 30 NM TO 60 NM ON EITHER SIDE OF 21N72W 26N74W 29N76W
TO 33N79W. A TROUGH ON WATER VAPOR IMAGERY PASSES THROUGH 33N39W 
TO 23N52W TO 23N59W TO 20N65W. THIS FEATURE SUPPORTS THE CENTRAL 
ATLANTIC SURFACE TROUGH THAT EXTENDS FROM A 1018 MB LOW PRESSURE 
CENTER NEAR 31N50W TO 27N45W 22N50W AND 20N58W. BROKEN TO 
OVERCAST MULTILAYERED CLOUDS AND POSSIBLE PRECIPITATION ARE 
WITHIN 60 NM TO 120 NM ON EITHER SIDE OF 21N65W 22N50W 27N40W
TO 32N39W. A 1024 MB HIGH PRESSURE CENTER IS NEAR 33N59W. 
SURFACE ANTICYCLONIC FLOW COVERS THE AREA TO THE NORTH OF 27N 
BETWEEN 55W AND 72W. AN UPPER LEVEL TROUGH IS ALONG THE COAST
OF MOROCCO NEAR 30N10W EXTENDING TO THE SOUTHERN PARTS OF THE
WESTERN SAHARA. CYCLONIC FLOW COVERS THE CANARY ISLANDS AND
THE MADEIRA ARCHIPELAGO.

$$
MT