000
AXNT20 KNHC 221748
TWDAT 

TROPICAL WEATHER DISCUSSION 
NWS TPC/NATIONAL HURRICANE CENTER MIAMI FL
205 AM EDT WED APR 22 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...
ITCZ AXIS IS CENTERED 4N9W CROSSING THE EQUATOR NEAR 23W TO NE 
BRAZIL NEAR 3S42W. SCATTERED MODERATE ISOLATED STRONG CONVECTION 
IS S OF 3N BETWEEN 20W-28W.

...DISCUSSION...
GULF OF MEXICO...
LARGE DEEP LAYER TROUGH OVER THE EASTERN U.S. EXTENDS INTO THE 
EASTERN GULF OF MEXICO. COLD FRONT WHICH MOVED THROUGH THE SE 
GULF TUE HAS IS SE OF THE AREA...HOWEVER A REINFORCING COLD IS 
JUST N OF TAMPA BAY TO 28N85W THEN STATIONARY TO MOBILE ALABAMA. 
THE FRONT IS MAINLY DRY AS SATELLITE IMAGERY ONLY INDICATES 
LITTLE CLOUD COVER ALONG THE BOUNDARY. SFC HIGH PRES CENTERED 
OVER THE CENTRAL GULF NEAR 24N88W COUPLED WITH DEEP LAYER DRY 
AIR IS PRODUCING MAINLY FAIR WEATHER AND LIGHT WINDS OVER THE 
REMAINDER OF THE GULF.

THE CARIBBEAN SEA... 
THE TAIL END OF A W ATLC COLD FRONT EXTENDS FROM CENTRAL CUBA 
NEAR 22N80W TO 21N82W THEN DISSIPATING TO BELIZE. THERE ARE A 
FEW SHOWERS ALONG THE FRONT. THE LARGE AREA OF VERY STRONG TSTMS 
IN THE SW CARIBBEAN ALONG THE COAST OF PANAMA AND COSTA RICA...S 
OF 12N W OF 81W...IS SLOWLY STARTING TO WEAKEN SOME. THIS 
CONVECTIVE ACTIVITY IS ENHANCED BY AN UPPER DIFFLUENT PATTERN. 
WLY FLOW ALOFT IS ADVECTING SOME MOISTURE FROM THIS AREA INTO 
THE CENTRAL AND ERN CARIBBEAN BUT IT APPEARS TO BE ONLY IN THE 
FORM OF MID-HIGH LEVEL CLOUDS. TRADE WINDS REMAIN IN THE 20-30 
KT RANGE OVER THE S CARIBBEAN...STRONGEST NEAR THE COAST OF 
COLOMBIA.

THE ATLANTIC OCEAN...
SCATTERED SHOWERS AND ISOLATED TSTMS ARE WITHIN 300 NM E OF A 
COLD FRONT EXTENDING FROM 32N70W TO CENTRAL CUBA. THIS ACTIVITY 
IS BEING ENHANCED BY STRONG SWLY UPPER FLOW AND A DIFFLUENT 
PATTERN BETWEEN THE ASSOCIATED UPPER TROUGH OVER THE ERN U.S. 
AND A RIDGE OVER THE CENTRAL ATLC. A SECONDARY FRONT ENTERS THE 
AREA NEAR 32N76W TO N FLORIDA NEAR 29N81W. A 90-100 KT JET 
STREAM E OF THE UPPER TROUGH FROM THE NORTHERN BAHAMAS TO 
32N72W. THE CENTRAL ATLC UPPER RIDGE HAS AXIS FROM 32N58W TO 
PUERTO RICO. DEEP LAYER TROUGH REMAINS WELL DEFINED FROM 32N38W 
TO 15N48W. A COLD FRONT EXTENDS FROM 32N35W TO 30N43W THEN 
CONTINUES AS A SURFACE TROUGH TO 26N59W. NO SIGNIFICANT WEATHER 
ASSOCIATED WITH THIS FEATURE AS THE AIR IS RATHER DRY. AN UPPER 
LEVEL RIDGE OVER THE EASTERN ATLC WITH AXIS ALONG THE E COAST OF 
AFRICA.

$$
DGS