000
AXNT20 KNHC 040501
TWDAT 

TROPICAL WEATHER DISCUSSION
NWS TPC/NATIONAL HURRICANE CENTER MIAMI FL
205 AM EDT FRI MAY 04 2007

TROPICAL WEATHER DISCUSSION FOR NORTH AMERICA...CENTRAL 
AMERICA...THE GULF OF MEXICO...THE CARIBBEAN SEA...NORTHEASTERN 
SECTIONS OF SOUTH AMERICA...AND THE 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 
0445 UTC.

...ITCZ...

ITCZ AXIS IS CENTERED ALONG 5N10W 2N20W 1N29W 1N52W. CLUSTERS OF 
SCATTERED MODERATE/STRONG CONVECTION ARE FROM THE SW AFRICA 
COAST TO ACROSS THE EQUATOR E OF 13W TO ACROSS THE PRIME 
MERIDIAN. CLUSTERS OF SCATTERED MODERATE/ISOLATED STRONG 
CONVECTION ARE FROM 6N TO ACROSS THE EQUATOR FROM 14W-27W AND 
WITHIN 75/90 NM OF LINE FROM 2N35W TO SOUTH AMERICA NEAR 5N53W. 

...DISCUSSION...

GULF OF MEXICO...
THE STRONG UPPER LOW IS MOVING FROM NE TEXAS INTO ARKANSAS 
GENERATING STRONG THUNDERSTORMS INLAND OVER SE LOUISIANA AND 
MISSISSIPPI WITH SCATTERED SHOWERS AND POSSIBLE ISOLATED 
THUNDERSTORMS ALSO IN NW GULF N OF 28N BETWEEN 90W-93W. THE W 
GULF IS DOMINATED BY A STRONG UPPER RIDGE THAT EXTENDS FROM THE 
E PACIFIC REGION ACROSS MEXICO TO THE N GULF COAST NEAR THE 
TEXAS/LOUISIANA BORDER AND IS PUSHING THE THUNDERSTORMS NE. THE 
UPPER TROUGH REMAINS OVER THE E GULF ACROSS FLORIDA INTO THE W 
ATLC WITH AN UPPER LOW MOVING S OVER FT MYERS FLORIDA. AS LAST 
NIGHT...STILL NO ASSOCIATED SURFACE REFLECTION. WEAK PRESSURE 
GRADIENT IS ACROSS THE GULF AND WITH THE DRY AIR IN PLACE THE 
REMAINDER OF THE GULF CLEAR SKIES AGAIN TONIGHT. 

CARIBBEAN SEA...
THE UPPER TROUGH IN THE E GULF OF MEXICO COVERS THE W CARIBBEAN 
TO CENTRAL AMERICA N OF 14N W OF 76W. BROAD UPPER RIDGE 
DOMINATES THE REMAINDER OF THE CARIBBEAN ANCHORED OVER E 
VENEZUELA. THIS UPPER RIDGE IS ADVECTING TROPICAL MOISTURE N 
ACROSS THE CENTRAL CARIBBEAN BETWEEN 70W-80W WITH POSSIBLE 
ISOLATED SHOWERS. THE ITCZ AXIS IN THE E PACIFIC REGION REMAINS 
OVER PORTIONS OF PANAMA AND COSTA RICA GENERATING SCATTERED 
SHOWERS/ THUNDERSTORMS S OF 12N TO INLAND OVER COLOMBIA TO COSTA 
RICA BETWEEN 75W-83W. OTHERWISE THE W AND E CARIBBEAN REMAIN DRY 
WITH CLEAR SKIES AND MODERATE EASTERLY TRADE WINDS USHERING IN 
SOME LOW LEVEL ISOLATED SHOWERS OVER THE NE CARIBBEAN N OF 15N E 
OF 70W.  

ATLANTIC...
UPPER TROUGH OVER THE E GULF OF MEXICO EXTENDS ACROSS FLORIDA 
INTO THE W ATLC W OF 73W. A REMNANT SURFACE TROUGH REMAINS 
EXTENDING FROM 30N73W ACROSS THE BAHAMA ISLANDS TO THE N COAST 
OF CUBA NEAR 21N75W. THE UPPER RIDGE FROM THE CARIBBEAN EXTENDS 
OVER THE REMAINDER OF THE W ATLC ALONG 63W ENHANCING CLUSTERS OF 
SCATTERED SHOWERS/ISOLATED THUNDERSTORMS BETWEEN 30N TO THE 
GREATER ANTILLES BETWEEN 72W AND THE SURFACE TROUGH WITH SOME 
ISOLATED THUNDERSTORMS S OF 28N TO 80W. THE REMAINDER OF THE 
ATLC IS UNDER BENIGN UPPER LEVEL TROUGH-RIDGE-TROUGH PRODUCING 
NO SIGNIFICANT WEATHER. BROAD SURFACE RIDGE COVERS THE ATLC E OF 
70W ANCHORED BY A 1029 MB HIGH S OF THE AZORES NEAR 35N28W. 
THIS SURFACE RIDGE COUPLED WITH THE DRY AIR IN PLACE IS GIVING 
THE REMINDER OF THE ATLC FAIR WEATHER AGAIN TONIGHT. 

$$
WALLACE