000
AXNT20 KNHC 221123
TWDAT 

TROPICAL WEATHER DISCUSSION
NWS TPC/NATIONAL HURRICANE CENTER MIAMI FL  
705 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 0600 UTC SURFACE ANALYSIS AND SATELLITE IMAGERY THROUGH 
1115 UTC.

...ITCZ...

THE ITCZ AXIS IS CENTERED ALONG 5N8W 4N20W 6N35W 2N51W. 
SCATTERED MODERATE CONVECTION IS FROM 4N-6N BETWEEN 21W-28W... 
AND FROM 4N-5N BETWEEN 28W-35W. WIDELY SCATTERED MODERATE 
CONVECTION IS FROM 3N-6N BETWEEN 47W-53W.  

...DISCUSSION...

GULF OF MEXICO...
A 1025 MB HIGH IS CENTERED OVER N FLORIDA NEAR 30N83W. 5-10 KT 
ANTICYCLONIC SURFACE WINDS DOMINATES THE GULF OF MEXICO. BROKEN 
TO OVERCAST MULTILAYERED CLOUDS ARE OVER FLORIDA...CUBA...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 92W. 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 AXIS TO MOVE E TO 82W IN 24 HOURS. 

CARIBBEAN SEA...
A WEAK STATIONARY FRONT IS OVER THE CARIBBEAN FROM HISPANIOLA TO 
JAMAICA TO THE SW CARIBBEAN ALONG 19N70W 17N80W 10N83W. A 1010 
MB LOW IS CENTERED OVER N COLOMBIA NEAR 11N75W. ISOLATED 
MODERATE CONVECTION IS OVER THE W CARIBBEAN FROM 7N-19N BETWEEN 
76W-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 EXTENDING S TO N COLOMBIA. 
ALSO EXPECT CONVECTION NEAR THIS LOW AND TROUGH.      

ATLANTIC OCEAN...
A COLD FRONT EXTENDS FROM THE CENTRAL ATLANTIC NEAR 32N34W TO 
HISPANIOLA ALONG 28N40W 22N60W 19N70W. WIDELY SCATTERED MODERATE 
CONVECTION IS FROM 25N-28N BETWEEN 35W-40W. SCATTERED MODERATE 
CONVECTION IS FURTHER E FROM 24N-26N BETWEEN 31W-33W. A 1016 MB 
HIGH IS OVER THE CENTRAL ATLANTIC NEAR 18N42W. A SURFACE TROUGH 
IS OVER THE E ATLANTIC NEAR THE CANARY ISLANDS ALONG 32N11W 
27N18W. SCATTERED SHOWERS ARE WITHIN 30 NM OF THE TROUGH N OF 
28N. IN THE UPPER LEVELS... AN UPPER LEVEL HIGH IS CENTERED E OF 
THE LESSER ANTILLES NEAR 13N58W. 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