000
AXNT20 KNHC 211055
TWDAT 

TROPICAL WEATHER DISCUSSION
NWS TPC/NATIONAL HURRICANE CENTER MIAMI FL
805 AM EDT THU MAY 21 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 0600 UTC SURFACE ANALYSIS AND SATELLITE IMAGERY
THROUGH 1015 UTC.

...TROPICAL WAVES...
A TROPICAL WAVE IS ALONG 70W TO THE SOUTH OF 11N MOVING WEST 
ABOUT 15 KT MOVING THROUGH WESTERN VENEZUELA. NUMEROUS STRONG
SHOWERS AND THUNDERSTORMS WERE OCCURRING BETWEEN LAKE MARACAIBO 
AND EXTREME NORTHEASTERN COLOMBIA SIX HOURS AGO. MOST OF THAT
PRECIPITATION HAS DISSIPATED. THE ONLY STRONG CONVECTIVE 
PRECIPITATION IS IN NORTHWESTERN COLOMBIA FROM 7N TO 9N BETWEEN 
76W AND 77W CLOSE TO ITS BORDER WITH PANAMA...PROBABLY HAVING
TO DO WITH THE ITCZ.

...THE ITCZ...

FROM SIERRA LEONE NEAR 8N13W TO 3N30W...CROSSING THE EQUATOR
ALONG 36W...INTO NORTHEASTERN BRAZIL NEAR 4S43W. ISOLATED
AND DISORGANIZED MODERATE SHOWERS ARE TO THE SOUTH OF 6N
TO THE EAST OF 40W.

...DISCUSSION...

THE GULF OF MEXICO...THE NORTH CENTRAL AND NORTHWESTERN 
CARIBBEAN SEA...AND PARTS OF THE ATLANTIC OCEAN TO THE
WEST OF 65W...
ONE MIDDLE LEVEL TO UPPER LEVEL CYCLONIC CIRCULATION CENTER
IS ABOUT 90 NM TO THE WEST OF PORT CHARLOTTE FLORIDA. A SECOND 
SUCH CYCLONIC CENTER IS MOVING TOWARD ST. AUGUSTINE FLORIDA.
A 1006 MB LOW PRESSURE CENTER IS NEAR 26N86W. ISOLATED MODERATE 
SHOWERS AND LOCALLY STRONG THUNDERSTORMS ARE IN THE CARIBBEAN
SEA FROM 16N TO 20N BETWEEN 70W AND 80W...AND FROM 20N TO 30N
BETWEEN 68W AND 85W IN THE ATLANTIC OCEAN...ACROSS FLORIDA...
INTO THE EASTERN GULF OF MEXICO.

THE REST OF THE CARIBBEAN SEA...
NUMEROUS STRONG SHOWERS AND THUNDERSTORMS WERE OCCURRING BETWEEN 
LAKE MARACAIBO AND EXTREME NORTHEASTERN COLOMBIA SIX HOURS AGO. 
MOST OF THAT PRECIPITATION HAS DISSIPATED. THE ONLY STRONG 
CONVECTIVE PRECIPITATION IS IN NORTHWESTERN COLOMBIA FROM 7N
TO 9N BETWEEN 76W AND 77W CLOSE TO ITS BORDER WITH PANAMA...
PROBABLY HAVING TO DO WITH THE ITCZ. AN UPPER LEVEL TROUGH CUTS 
ACROSS THE ISLANDS OF THE EASTERN CARIBBEAN SEA REACHING A BASE 
NEAR 7N57W IN THE ATLANTIC OCEAN. 

THE ATLANTIC OCEAN TO THE EAST OF 65W...
A NEW MIDDLE LEVEL TO UPPER LEVEL CYCLONIC CIRCULATION CENTER 
HAS FORMED AND IS MOVING TO A SPOT ABOUT 90 NM TO THE SOUTH OF 
BERMUDA. NO DEEP CONVECTIVE PRECIPITATION ACCOMPANIES THIS 
FEATURE AT THIS TIME. A PERSISTENT AND NOW BROAD DEEP LAYER 
CENTRAL ATLANTIC OCEAN CYCLONIC CIRCULATION CENTER HAS MOVED TO
32N48W ON WATER VAPOR SATELLITE IMAGERY. A 1014 MB LOW PRESSURE 
CENTER IS NEAR 29N54W AT THE SURFACE. BROAD CYCLONIC FLOW ON 
WATER VAPOR IMAGERY COVERS THE ATLANTIC OCEAN FROM 22N TO 37N 
BETWEEN 37W AND 60W. THE TROUGH FROM SIX HOURS AGO WAS DROPPED
FROM THE ANALYSIS. ISOLATED MODERATE SHOWERS ARE FROM 25N TO 33N 
BETWEEN 42W AND 50W. AN EASTERN ATLANTIC OCEAN DEEP LAYER TROUGH 
SUPPORTS THE CURRENT COLD FRONT THAT PASSES THROUGH 32N17W TO 
26N26W TO 27N33W. THE FRONT IS MARKED BY A SOLID LINE OF BROKEN 
TO OVERCAST MULTILAYERED CLOUDS AND POSSIBLE PRECIPITATION.

$$
MT