000
AXNT20 KNHC 012337
TWDAT 

TROPICAL WEATHER DISCUSSION
NWS TPC/NATIONAL HURRICANE CENTER MIAMI FL  
705 PM EST FRI JAN 01 2010

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 1800 UTC SURFACE ANALYSIS AND SATELLITE IMAGERY THROUGH 
2315 UTC.

...THE ITCZ...
THE ITCZ AXIS IS CENTERED ALONG 8N12W 5N30W 4N45W 2N51W. 
SCATTERED MODERATE CONVECTION IS ALONG THE COAST OF LIBERIA FROM 
4N-6N BETWEEN 7W-10W. SIMILAR CONVECTION IS OFF THE COAST OF 
SIERRA LEONE FROM 6N-8N BETWEEN 14W-16W. ISOLATED MODERATE 
CONVECTION IS FROM 3N-5N BETWEEN 20W-23W...AND FROM 2N-4N 
BETWEEN 40W-44W.

...DISCUSSION...

GULF OF MEXICO...
AS OF 2100 UTC...A COLD FRONT EXTENDS FROM THE STRAITS OF 
FLORIDA TO THE YUCATAN PENINSULA ALONG 25N80W 21N90W 18N93W. 
RADAR IMAGERY SHOWS A BAND OF RAIN AND SHOWERS OVER THE STRAITS 
OF FLORIDA FROM 23N-25N BETWEEN 80W-83W MOVING SE. 20-25 KT 
NORTHERLY WINDS ARE OVER THE E GULF OF MEXICO N OF THE FRONT. 
TEMPERATURES DROPPED 15 DEGREES OVER SOUTH FLORIDA WITH FRONTAL 
PASSAGE. A 1031 MB HIGH IS CENTERED NEAR TAMPICO MEXICO AT 
22N98W. THIS HIGH HAS TIGHTENED THE SURFACE PRESSURE GRADIENT 
AND A GALE IS OVER THE SW GULF OF MEXICO S OF 23N W OF 95W. IN 
THE UPPER LEVELS...ZONAL FLOW IS OVER THE GULF AND 90-110 KT 25O 
MB WINDS ARE NOTED OVER THE N GULF N OF 25N. UPPER LEVEL 
MOISTURE WITH BROKEN HIGH CLOUDS ARE OVER THE S GULF S OF 25N.  
EXPECT IN 12 HOURS...FOR THE COLD FRONT TO MOVE SE OF THE GULF. 
25-30 KT NORTHERLY WINDS WILL BE BEHIND THIS FRONT WITH A LOT OF 
COLD AIR ADVECTION.  

CARIBBEAN SEA...
THE TAIL END OF A FRONTAL TROUGH IS OVER THE LEEWARD 
ISLANDS...AND SOUTH OF PUERTO RICO AND HISPANIOLA ALONG 14N60W 
17N70W 17N73W. BROKEN TO OVERCAST LOW CLOUDS WITH SCATTERED 
SHOWERS ARE WITHIN 60 NM OF THE TROUGH. 15-20 KT NE WINDS ARE 
NORTH OF THE TROUGH. FRESH TRADEWINDS ARE OVER THE REMAINDER 
CARIBBEAN SEA AND CENTRAL AMERICA. BROKEN TO OVERCAST LOW CLOUDS 
WITH SCATTERED SHOWERS ARE THE W CARIBBEAN AND CENTRAL AMERICA 
FROM 8N-22N W OF 82W. IN THE UPPER LEVELS...AN UPPER LEVEL HIGH 
IS CENTERED OVER COSTA RICA NEAR 10N84W. ZONAL FLOW IS OVER THE 
E CARIBBEAN E OF 70W. VERY STRONG SUBSIDENCE IS OVER THE 
CARIBBEAN AND CENTRAL AMERICA EXCEPT OVER THE NW CARIBBEAN N OF 
17N W OF 80W WHERE UPPER LEVEL MOISTURE IS NOTED. THE SUBSIDENCE 
IS SUPPRESSING DEEP CONVECTION OVER THE AREA. EXPECT IN 24 HOURS 
FOR THE GULF OF MEXICO COLD FRONT TO EXTEND FROM E CUBA TO 
BELIZE WITH RAIN AND THUNDERSTORMS. ALSO EXPECT CONTINUED 
SHOWERS S OF HISPANIOLA.   

ATLANTIC OCEAN...
AS OF 2100 UTC...A COLD FRONT IS OVER THE W ATLANTIC FROM 32N73W 
TO THE STRAITS OF FLORIDA NEAR 25N80W MOVING SE. OVERCAST 
MULTILAYERED CLOUDS WITH RAIN AND SHOWERS ARE WITHIN 120 NM OF 
THE FRONT. NORTHERLY WINDS ARE N OF THE FRONT BRINGING ALONG A 
LOT OF COLD AIR ADVECTION. GALE FORCE WINDS ARE N OF 27N E OF 
THE FRONT TO 58W. FURTHER E...A 1022 MB HIGH IS CENTERED OVER 
THE CENTRAL ATLANTIC NEAR 29N56W MOVING E. A COLD FRONT EXTENDS 
FROM THE EASTERN ATLANTIC NEAR 32N27W TO E OF THE LEEWARD 
ISLANDS ALONG 24N34W 16N50W. A DISSIPATING COLD FRONT CONTINUES 
TO THE LEEWARD ISLANDS NEAR 14N60W. SCATTERED MODERATE 
CONVECTION IS WITHIN 180 NM E OF THE FRONT N OF 22N. SCATTERED 
SHOWERS ARE WITHIN 60 NM OF THE REMAINDER OF THE FRONTS. IN THE 
UPPER LEVELS...A RIDGE IS OVER THE W ATLANTIC W OF 50W. AN UPPER 
LEVEL TROUGH IS FURTHER E OVER THE CENTRAL ATLANTIC BETWEEN 
30W-50W. UPPER LEVEL ZONAL FLOW IS OVER THE REMAINDER OF THE 
ATLANTIC. EXPECT OVER THE NEXT 24 HOURS...FOR THE W ATLANTIC 
FRONT TO MOVE SE TO THE CENTRAL ATLANTIC NEAR 58W WITH 
CONVECTION. ALSO EXPECT THE E ATLANTIC COLD FRONT TO MOVE E AND 
REACH THE CANARY ISLANDS WITH SHOWERS AND CONVECTION.    

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

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FORMOSA