000
AXNT20 KNHC 221738
TWDAT 

TROPICAL WEATHER DISCUSSION
NWS TPC/NATIONAL HURRICANE CENTER MIAMI FL  
105 PM 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 1200 UTC SURFACE ANALYSIS AND SATELLITE IMAGERY THROUGH 
1730 UTC.

...ITCZ...

THE ITCZ AXIS IS CENTERED ALONG 4N9W 3N22W 3N34W AND 4N50W. WEAK 
TO MODERATE CONVECTION IS FOUND EAST AND NORTH OF FRENCH 
GUIANA...AND NORTH OF THE ITCZ FROM 3N TO 7N BETWEEN 23W AND 
40W. ISOLATED WEAK TO MODERATE CONVECTION IS WEST OF CENTRAL 
LIBERIA.  

...DISCUSSION...

GULF OF MEXICO...
A 1025 MB HIGH IS CENTERED OVER SOUTHERN GEORGIA NEAR 30N83W. 
THEREFORE FAIR WEATHER DUE TO STRONG SUBSIDENCE IS COVERING THE 
GULF OF MEXICO...WITH 5-10 KT ANTICYCLONIC SURFACE WINDS 
DOMINATING OVER THE BASIN. MODEL DATA INDICATES LIGHT WEST FLOW 
ALOFT WITH AN UPPER LEVEL TROUGH OVER THE GULF WITH AXIS ALONG 
87W. HOWEVER...VERY LITTLE MOISTURE IS BEEN MOVED IN THE UPPER 
LEVEL ATMOSPHERE. LIGHT SURFACE FLOW WILL REMAIN OVER THE NEXT 
24 HOURS...WITH UPPER LEVEL TROUGH AXIS MOVING EAST TO NEAR 82W. 

CARIBBEAN SEA...
A STATIONARY FRONT IS ANALYZED FROM CENTRAL DOMINICAN REPUBLIC 
TO THE SOUTHWEST ALONG 17N75W 15N78W 11N80W. A 1010 MB LOW IS 
CENTERED OVER N COLOMBIA NEAR 09N76W. ISOLATED MODERATE 
CONVECTION IS EAST OF THE STATIONARY FRONT FROM 10N-20N BETWEEN 
80W-73W. SOUTHWEST UPPER LEVEL FLOW FROM UPPER LEVEL TROUGH OVER 
WESTERN CARIBBEAN IS BRINGING SUFFICIENT MOISTURE TO MAINTAIN 
THE WEATHER ACTIVITY IN THIS REGION. OTHERWISE...MOSTLY FAIR 
WEATHER IS FOUND EAST OF 72W DUE TO STRONG SUBSIDENCE IN THIS 
AREA. BUOY AND SHIP OBSERVATIONS SHOW EASTERLY WINDS 10-20 KTS 
ACROSS THE BASIN. EXPECT OVER THE NEXT 24 HOURS FOR THE 
STATIONARY FRONT TO DISSIPATE AND A SURFACE LOW TO FORM OVER 
SOUTHEAST JAMAICA...PRODUCING ADDITIONAL CONVECTION IN THIS 
AREA.      

ATLANTIC OCEAN...
A COLD FRONT EXTENDS ACROSS THE CENTRAL ATLANTIC NEAR 30N28W TO 
HISPANIOLA ALONG 26N35W 24N44W 21N56W. WINDS BEHIND THE FRONT 
HAVE INCREASED TO GALE FORCE NORTH OF 26 BETWEEN 42W AND 55W. A 
BROAD AREA OF SCATTERED MODERATE CONVECTION IS FOUND EAST OF THE 
FRONT FROM 25N-30N BETWEEN 16W-35W. OTHERWISE...FAIR WEATHER IS 
SEEN OVER THE WESTERN ATLANTIC AS 1024 MB HIGH PRESSURE ENTERS 
THE REGION. ANOTHER 1017 MB HIGH IS OVER THE CENTRAL ATLANTIC 
NEAR 17N40W. LOOKING AT UPPER LEVEL DATA...AN UPPER LEVEL HIGH 
COVERS MOST OF THE SOUTHERN ATLANTIC. LOOK FOR THE COLD FRONT TO 
EXPAND EASTWARD OVER THE NEXT 24 HOURS WITH WITH FURTHER 
CONVECTION MOVING TO THE EAST ATLANTIC.   

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

$$

GARCIA