000
AXNT20 KNHC 210605
TWDAT 

TROPICAL WEATHER DISCUSSION
NWS TPC/NATIONAL HURRICANE CENTER MIAMI FL
205 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 0000 UTC SURFACE ANALYSIS AND SATELLITE IMAGERY
THROUGH 0515 UTC.

...TROPICAL WAVES...
A TROPICAL WAVE IS ALONG 68W/69W TO THE SOUTH OF 11N MOVING
WEST ABOUT 15 KT MOVING THROUGH WESTERN VENEZUELA. ANY AND
ALL NEARBY PRECIPITATION HAS BEEN WEAKENING/DISSIPATING
DURING THE LAST SIX HOURS. STRONG SHOWERS AND THUNDERSTORMS
HAVE DEVELOPED BETWEEN LAKE MARACAIBO AND EXTREME NORTHEASTERN
COLOMBIA. IT IS EASILY POSSIBLE THAT THE COLOMBIA PRECIPITATION
MAY HAVE TO DO WITH THE ITCZ.

...THE ITCZ...

FROM SIERRA LEONE NEAR 8N13W TO 3N30W...CROSSING THE EQUATOR
ALONG 36W...INTO NORTHEASTERN BRAZIL NEAR 4S42W. ISOLATED AND
DISORGANIZED MODERATE SHOWERS ARE TO THE SOUTH OF 8N
TO THE EAST OF 40W.

...DISCUSSION...

THE GULF OF MEXICO...THE NORTHWESTERN CARIBBEAN SEA...AND
THE ATLANTIC OCEAN TO THE WEST OF 70W...
ONE MIDDLE LEVEL TO UPPER LEVEL CYCLONIC CIRCULATION CENTER IS
ABOUT 60 NM TO THE WEST OF FORT MYERS FLORIDA. A SECOND SUCH
CYCLONIC CENTER IS ABOUT 80 NM TO THE EAST OF DAYTONA BEACH 
FLORIDA. A 1007 MB LOW PRESSURE CENTER IS NEAR 25N85W. A SURFACE
TROUGH EXTENDS FROM THE LOW CENTER TO THE FLORIDA WEST COAST
NEAR 27N82W...TO CUBA NEAR 23N80W...ON TOP OF GRAND CAYMAN 
ISLAND...TO 15N82W JUST TO THE EAST OF THE EASTERN BORDER
OF HONDURAS AND NICARAGUA. ISOLATED MODERATE TO STRONG SHOWERS 
AND THUNDERSTORMS ARE FROM CUBA TO NORTHERN FLORIDA AND THE 
ATLANTIC OCEAN FROM 21N TO 30N BETWEEN 73W AND 83W IN THE 
EASTERN GULF OF MEXICO.

THE REST OF THE CARIBBEAN SEA...
NUMEROUS STRONG SHOWERS AND THUNDERSTORMS ARE IN NORTHEASTERN 
COLOMBIA AND IN EXTREME NORTHWESTERN VENEZUELA...ALONG THE
ITCZ AND IN AN AREA OF BROAD LOW LEVEL CYCLONIC WIND FLOW.
BROAD AND GENERAL WESTERLY WIND FLOW COVERS THE AREA. AN UPPER 
LEVEL TROUGH CUTS ACROSS THE ISLANDS OF THE EASTERN CARIBBEAN 
SEA REACHING A BASE NEAR 10N60W. UPPER LEVEL ANTICYCLONIC FLOW 
MOVES AWAY FROM VENEZUELA...ACROSS THE EXTREME SOUTHEASTERN 
CORNER OF THE AREA...INTO THE OPEN WATERS OF THE ATLANTIC OCEAN 
BEYOND 23N48W.

THE ATLANTIC OCEAN TO THE EAST OF 70W...
A NEW MIDDLE LEVEL TO UPPER LEVEL CYCLONIC CIRCULATION CENTER 
HAS FORMED AND IS MOVING TO A SPOT ABOUT 50 NM TO THE EAST OF 
BERMUDA. NO DEEP CONVECTIVE PRECIPITATION ACCOMPANIES THIS 
FEATURE AT THIS TIME. A PERSISTENT DEEP LAYER CENTRAL ATLANTIC 
OCEAN CYCLONIC CIRCULATION CENTER IS NEAR 30N52W ON WATER VAPOR 
SATELLITE IMAGERY. A 1015 MB LOW PRESSURE CENTER IS NEAR 30N55W 
AT THE SURFACE. BROAD CYCLONIC FLOW ON WATER VAPOR IMAGERY 
COVERS THE ATLANTIC OCEAN FROM 22N TO 37N BETWEEN 37W AND 60W.
A SURFACE TROUGH IS ALONG THE LINE 26N50W 22N54W 21N65W. 
ISOLATED MODERATE SHOWERS ARE FROM 24N TO 34N BETWEEN 43W AND 
52W. AN EASTERN ATLANTIC OCEAN DEEP LAYER TROUGH SUPPORTS THE 
CURRENT COLD FRONT THAT PASSES THROUGH 32N20W TO 28N25W TO 
28N22W. THE FRONT IS MARKED BY A SOLID LINE OF BROKEN TO 
OVERCAST MULTILAYERED CLOUDS AND POSSIBLE PRECIPITATION.

$$
MT