000
AXNT20 KNHC 211707
TWDAT 

TROPICAL WEATHER DISCUSSION
NWS TPC/NATIONAL HURRICANE CENTER MIAMI FL
105 PM EST SAT FEB 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 1200 UTC SURFACE ANALYSIS AND SATELLITE IMAGERY THROUGH 
1645 UTC.

...THE ITCZ...

THE ITCZ AXIS IS CENTERED ALONG 5N5W 2N10W 1N20W 1N40W AND INTO 
NE BRAZIL NEAR EQ50W. NO DEEP CONVECTION IS ALONG THE ITCZ AXIS. 
WIDELY SCATTERED MODERATE CONVECTION IS INLAND OVER NE BRAZIL 
FROM 2S-EQ BETWEEN 46W-52W.  

...DISCUSSION...

GULF OF MEXICO...
A 1028 MB HIGH CENTERED OVER NORTH CAROLINA EXTENDS A RIDGE AXIS 
S TO THE YUCATAN PENINSULA PRODUCING 10-15 KT EASTERLY RETURN 
FLOW OVER THE GULF OF MEXICO. THE W GULF HAS BROKEN TO OVERCAST 
MULTILAYERED CLOUDS W OF 88W WITH ISOLATED SHOWERS. THE 
REMAINDER OF THE GULF HAS FAIR WEATHER. A COLD FRONT IS OVER 
CENTRAL TEXAS MOVING SE TOWARDS THE GULF. IN THE UPPER LEVELS... 
ZONAL FLOW COVERS THE GULF WITH SIGNIFICANT UPPER LEVEL MOISTURE 
W OF 90W. STRONG SUBSIDENCE COVER THE REMAINDER OF THE GULF. 
EXPECT THE COLD FRONT TO ENTER THE GULF THIS AFTERNOON WITH 
CONVECTION AND EXTEND FROM N FLORIDA TO THE BAY OF CAMPECHE IN 
24 HOURS.  

CARIBBEAN SEA...
A TIGHT PRESSURE GRADIENT BETWEEN THE NORTH CAROLINA HIGH AND A 
1007 MB LOW OVER N COLOMBIA IS PRODUCING STRONG TRADEWINDS 
OVER THE CARIBBEAN SEA AND CENTRAL AMERICA. A GALE IS ALONG THE 
COAST OF N COLOMBIA FROM 10N-13N BETWEEN 75W-77W. PATCHES OF 
BROKEN LOW CLOUDS AND SCATTERED SHOWERS DOTS THE AREA ESPECIALLY 
OVER THE E CARIBBEAN E OF 75W...AND OVER CENTRAL AMERICA FROM 
PANAMA TO E GUATEMALA. IN THE UPPER LEVELS...AN UPPER LEVEL 
RIDGE IS OVER THE CARIBBEAN WITH AXIS ALONG 65W. STRONG 
SUBSIDENCE COVERS THE ENTIRE AREA. EXPECT MORE SHOWERS OVER THE 
W CARIBBEAN W OF 78W OVER THE NEXT 24 HOURS.    

ATLANTIC OCEAN...
A COLD FRONT EXTENDS FROM 32N59W TO THE S BAHAMAS NEAR 23N73W. 
SCATTERED SHOWERS ARE WITHIN 90 NM OF THE FRONT. A 1035 MB HIGH 
IS OVER THE CENTRAL ATLANTIC NEAR 40N36W. A RIDGE AXIS EXTENDS 
SW TO 25N57W. A SURFACE TROUGH IS OVER THE E ATLANTIC ALONG 
32N28W 27N24W. SCATTERED SHOWERS ARE WITHIN 90 NM OF THE TROUGH. 
IN THE UPPER LEVELS... A LARGE UPPER LEVEL RIDGE IS OVER THE W 
ATLANTIC W OF 50W. A LARGE UPPER LEVEL LOW IS OVER THE E 
ATLANTIC CENTERED NEAR 30N26W. A TROUGH AXIS EXTENDS SW FROM THE 
LOW CENTER TO 5N45W. EXPECT THE TAIL END OF THE FRONT OVER THE W 
ATLANTIC TO LIFT N AND MERGE WITH THE COLD FRONT OVER N FLORIDA 
IN 24 HOURS        

$$
FORMOSA