000
AXNT20 KNHC 172335
TWDAT 

TROPICAL WEATHER DISCUSSION 
NWS TPC/NATIONAL HURRICANE CENTER MIAMI FL
805 PM EDT FRI APR 17 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 1800 UTC SURFACE ANALYSIS AND SATELLITE IMAGERY
THROUGH 2315 UTC. 

...THE ITCZ...
THE ITCZ AXIS EXTENDS FROM LIBERIA AT 5N10W TO THE EQUATOR AT 
20W TO 1S30W TO NE BRAZIL AT 1S48W. SCATTERED MODERATE 
CONVECTION IS FROM 2S-4S BETWEEN 10W-13W. WIDELY SCATTERED 
MODERATE CONVECTION IS OFF THE COAST OF BRAZIL FROM 1N-2S 
BETWEEN 41W-46W.

...DISCUSSION...

THE GULF OF MEXICO...
A DISSIPATING STATIONARY FRONT DEPICTED BY LOW CLOUDS EXTENDS 
FROM W CUBA TO THE MOUTH OF THE MISSISSIPPI RIVER ALONG 23N83W 
29N89W. WINDS ARE EASTERLY 15-20 KT E OF THE FRONT... AND 
SOUTHEASTERLY 15-20 KT W OF THE FRONT. A PLUME OF SMOKE IS OVER 
THE W GULF OF MEXICO AND THE BAY OF CAMPECHE W OF 95W MOVING NW. 
AN OUTFLOW BOUNDARY IS ALONG THE TEXAS AND LOUISIANA COASTS. 
SCATTERED MODERATE TO ISOLATED STRONG CONVECTION IS N OF 28N 
BETWEEN 92W-98W. IN THE UPPER LEVELS...ZONAL FLOW DOMINATES THE 
ENTIRE GULF. CONSIDERABLE UPPER LEVEL MOISTURE IS OVER THE W 
GULF W OF 90W WHILE STRONG SUBSIDENCE IS OVER THE E GULF. 
EXPECT...A 1008 MB LOW TO BE OVER N LOUISIANA IN 24 HOURS WITH A 
COLD FRONT EXTENDING S FROM THE LOW CENTER TO S TEXAS NEAR 
BROWNSVILLE WITH CONVECTION. THE MAJORITY OF THE GULF OF MEXICO 
WILL HAVE CONTINUED RETURN SOUTHEASTERLY FLOW OVER THE NEXT 24 
HOURS.       

THE CARIBBEAN SEA...
A DISSIPATING COLD FRONT IS OVER CUBA ALONG 20N74W 20N78W 
23N83W. SCATTERED SHOWERS ARE WITHIN 60 NM N OF THE FRONT. 
CLUSTERS OF SCATTERED MODERATE CONVECTION ARE OVER INLAND N 
COLOMBIA AND NW VENEZUELA FROM 8N-11N BETWEEN 70W-76W. FRESH 
TRADEWINDS ARE OVER THE CARIBBEAN AND CENTRAL AMERICA WITH 
STRONGEST WINDS ALONG THE COAST OF N COLOMBIA. SCATTERED SHOWERS 
ARE OVER THE HIGHER ELEVATIONS OF PUERTO RICO...HISPANIOLA... 
JAMAICA...AND CUBA. MORE SCATTERED SHOWERS ARE ALONG THE COAST 
OF COSTA RICA. IN THE UPPER LEVELS...ZONAL FLOW IS OVER THE W 
CARIBBEAN AND CENTRAL AMERICA W OF 80W. AN UPPER LEVEL RIDGE IS 
OVER THE REMAINDER OF THE CARIBBEAN E OF 80W PRODUCING SW UPPER 
LEVEL WINDS. EXPECT...MORE SCATTERED SHOWERS OVER THE NEXT 24 
HOURS ESPECIALLY OVER THE S CARIBBEAN S OF 12N.         

THE ATLANTIC OCEAN...
A COLD FRONT IS OVER THE W ATLANTIC FROM 32N54W TO E CUBA AT 
20N74W. WIDELY SCATTERED MODERATE CONVECTION IS WITHIN 60 NM OF 
THE FRONT N OF 28N. A 1025 MB HIGH IS OVER THE E ATLANTIC NEAR 
30N31W. THE REMNANTS OF A FRONTAL TROUGH IS FURTHER E ALONG 
32N13W 27N27W. IN THE UPPER LEVELS...ZONAL FLOW IS OVER THE W 
ATLANTIC N OF 20N W OF 50W. AN UPPER LEVEL RIDGE IS OVER THE 
CENTRAL ATLANTIC N OF 20N BETWEEN 15W-50W. A BROAD RIDGE IS OVER 
THE TROPICAL ATLANTIC S OF 20N W OF 30W. EXPECT...THE COLD THE 
COLD FRONT TO MOVE SLIGHTLY E OVER THE NEXT 24 HOURS AND EXTEND 
FROM 32N50W TO N OF THE VIRGIN ISLANDS IN 24 HOURS WITH 
SHOWERS.   

$$
FORMOSA