000
AXNT20 KNHC 220539
TWDAT 

TROPICAL WEATHER DISCUSSION
NWS TPC/NATIONAL HURRICANE CENTER MIAMI FL  
105 AM EST TUE DEC 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 0000 UTC SURFACE ANALYSIS AND SATELLITE IMAGERY THROUGH 
0515 UTC.

...ITCZ...

THE ITCZ AXIS IS CENTERED ALONG 6N10W 4N20W 4N45W 3N51W. 
ISOLATED MODERATE CONVECTION IS FROM 4N-5N BETWEEN 26W-32W. 

...DISCUSSION...

GULF OF MEXICO...
A 1025 MB HIGH IS CENTERED OFF THE COAST OF THE FLORIDA 
PANHANDLE NEAR 30N87W. 5-10 KT ANTICYCLONIC SURFACE WINDS 
DOMINATES THE GULF OF MEXICO. BROKEN TO OVERCAST MULTILAYERED 
CLOUDS ARE OVER FLORIDA... THE SE GULF... AND THE YUCATAN 
PENINSULA. THE REMAINDER OF THE GULF HAS MOSTLY FAIR SKIES.  
IN THE UPPER LEVELS...A VERY SHARP TROUGH IS OVER THE GULF WITH 
AXIS ALONG 94W. UPPER LEVEL MOISTURE AND CLOUDS ARE AS NOTED 
ABOVE WHILE STRONG SUBSIDENCE IS OVER THE REMAINDER OF THE GULF. 
EXPECT OVER THE NEXT 24 HOURS... VERY LITTLE CHANGE IN THE 
SURFACE FLOW. ALSO EXPECT THE UPPER LEVEL TROUGH TO MOVE E WITH 
AXIS OVER 83W IN 24 HOURS. 

CARIBBEAN SEA...
A WEAK STATIONARY FRONT IS OVER THE CARIBBEAN FROM HISPANIOLA TO 
JAMAICA TO THE SW CARIBBEAN ALONG 20N70W 17N80W 14N83W 10N83W. A 
SURFACE TROUGH IS AHEAD OF THE FRONT EXTENDING FROM S OF JAMAICA 
TO PANAMA. ISOLATED MODERATE CONVECTION IS OVER THE CENTRAL 
CARIBBEAN FROM 9N-18N BETWEEN 78W-82W. MOSTLY FAIR WEATHER IS 
OVER THE E CARIBBEAN E OF 75W. 20 KT NE WINDS ARE OVER THE NW 
CARIBBEAN N OF THE STATIONARY FRONT. FRESH TRADEWINDS ARE S OF 
THE FRONT OVER THE CENTRAL CARIBBEAN WHILE MODERATE TRADEWINDS 
ARE OVER THE E CARIBBEAN E OF 70W. IN THE UPPER LEVELS...A RIDGE 
IS PRODUCING SW UPPER LEVEL WINDS OVER THE ENTIRE CARIBBEAN. 
SIGNIFICANT UPPER LEVEL MOISTURE IS OVER THE W CARIBBEAN W OF 
70W WHILE STRONG SUBSIDENCE IS OVER THE E CARIBBEAN. EXPECT OVER 
THE NEXT 24 HOURS FOR THE STATIONARY FRONT TO DISSIPATE AND A 
SURFACE LOW TO FORM OVER JAMAICA WITH A TROUGH TROUGH EXTENDING 
S TO N COLOMBIA. ALSO EXPECT CONVECTION NEAR THIS LOW AND 
TROUGH.      

ATLANTIC OCEAN...
A COLD FRONT EXTENDS FROM THE CENTRAL ATLANTIC NEAR 32N37W TO 
HISPANIOLA ALONG 25N50W 20N70W. ISOLATED MODERATE CONVECTION IS 
FROM 25N-28N BETWEEN 40W-45W. SCATTERED MODERATE CONVECTION IS 
FURTHER E FROM 24N-26N BETWEEN 32W-35W...AND FROM 25N-29N 
BETWEEN 24W-28W. A 1018 MB HIGH IS OVER THE CENTRAL ATLANTIC 
NEAR 18N38W. A SURFACE TROUGH IS OVER THE E ATLANTIC NEAR THE 
CANARY ISLANDS ALONG 32N12W 28N16W 25N20W. SCATTERED SHOWERS ARE 
WITHIN 60 NM OF THE TROUGH N OF 27N. IN THE UPPER LEVELS... AN 
UPPER LEVEL HIGH IS CENTERED E OF THE LESSER ANTILLES NEAR 
15N58W. UPPER LEVEL ANTICYCLONIC FLOW IS BETWEEN 40W-80W. AN 
UPPER LEVEL TROUGH IS OVER THE E ATLANTIC E OF 40W. EXPECT OVER 
THE NEXT 24 HOURS FOR THE COLD FRONT TO MOVE E WITH CONVECTION 
WHILE LITTLE CHANGE IS EXPECTED IN THE UPPER LEVELS.   

FOR ADDITIONAL INFORMATION PLEASE VISIT 
HTTP://WWW.HURRICANES.GOV/MARINE.

$$
FORMOSA