000
AXNT20 KNHC 301749
TWDAT 

TROPICAL WEATHER DISCUSSION
NWS TPC/NATIONAL HURRICANE CENTER MIAMI FL
205 PM EDT THU APR 30 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
1715 UTC.

...THE ITCZ...

THE ITCZ AXIS EXTENDS FROM W AFRICA AT 7N11W TO THE EQUATOR AT 
27W THEN CONTINUES S OF THE EQUATOR TO NE BRAZIL NEAR 3S39W. 
SCATTERED MODERATE/ISOLATED STRONG CONVECTION IS ALONG THE COAST 
OF LIBERIA EXTENDING INTO THE ADJACENT COASTAL WATERS FROM 4N-8N 
BETWEEN 7W-12W. CLUSTERS OF SCATTERED MODERATE CONVECTION ARE 
WITHIN 100 NM OF THE AXIS BETWEEN 23W-30W AND BETWEEN 35W-39W.   

...DISCUSSION...

GULF OF MEXICO...
A SURFACE RIDGE EXTENDS FROM HIGH PRESSURE ACROSS THE W ATLC 
THROUGH NORTH FLORIDA AND ALONG THE NRN GULF COAST. BUOYS AND AN 
EARLIER SCATTEROMETER PASS AROUND 1130 UTC SHOW SE RETURN FLOW 
OVER THE WRN GULF W OF 92W REACHING 15 TO 20 KT...BETWEEN THE 
HIGH PRESSURE RIDGE AND LOW PRESSURE OVER THE SRN PLAINS AND NRN 
MEXICAN PLATEAU. OTHER OBSERVATIONS THROUGH THE MORNING SHOW ELY 
WINDS TO 20 KT PERSISTING THROUGH THE STRAITS OF FLORIDA AND 
INTO THE SE GULF WATERS WHERE CONVERGENCE IS GENERATING ISOLATED 
SHOWER ACTIVITY S OF 26N E OF 85W. LOOKING AHEAD...THE SURFACE 
RIDGE REMAINS NEARLY STATIONARY WITH AXIS ORIENTED ALONG THE NRN 
GULF COAST AND LITTLE CHANGE IS EXPECTED OVER THE NEXT 24 HOURS. 

CARIBBEAN SEA...
SURFACE HIGH PRESSURE ACROSS THE W ATLC IS MAINTAINING GENERALLY 
15 TO 20 KT TRADE WIND FLOW ACROSS THE NORTHERN CARIBBEAN WITH 
SLIGHTLY HIGHER 15 TO 20 KT ELY FLOW S OF 15N. SCATTERED 
MODERATE SHOWERS IN THE TRADE WIND FLOW PERSIST...MAINLY OVER 
THE LESSER ANTILLES AND IN THE N/CENTRAL CARIBBEAN N OF 15N 
BETWEEN 66W-75W. LITTLE CHANGE IS EXPECTED OVER THE NEXT COUPLE 
OF DAYS AS THE HIGH PRESSURE RIDGE REMAINS ANCHORED IN THE W 
ATLC.
   
ATLANTIC OCEAN...
W OF 50W...UPPER TROUGHING IS ACROSS THE W ATLC AND COMING INTO 
PHASE WITH AN UPPER LOW SE OF BERMUDA NEAR 29N62W. AT THE 
SURFACE...A HIGH PRESSURE RIDGE IS POSITIONED ALONG 30N W OF 65W 
OVER THE W ATLC...AHEAD OF A FRONTAL BOUNDARY STALLING N OF THE 
AREA ASSOCIATED WITH THE UPPER TROUGHING. E OF THE UPPER LOW... 
AN AREA OF MIDDLE TO UPPER LEVEL DIFFLUENCE ALONG WITH AN 
INVERTED SURFACE TROUGH NE OF THE LEEWARDS EXTENDING FROM 20N62W 
TO 26N58W IS GENERATING SCATTERED SHOWERS FROM 20N-31N BETWEEN 
50W-62W. E OF 50W...A SURFACE RIDGE EXTENDS FROM A 1028 MB HIGH 
CENTERED NEAR 33N26W TO A 1027 MB HIGH NEAR 29N47W WITH 20 TO 25 
KT NE SURFACE FLOW NOTED OFF THE NW AFRICAN COAST. ELSEWHERE 
ACROSS THE TROPICAL ATLC...FAIR WEATHER CONDITIONS DOMINATE 
UNDER GENERALLY 15 TO 20 KT NE TO ELY TRADE WINDS.

$$
HUFFMAN