000
AXNT20 KNHC 041138
TWDAT 

TROPICAL WEATHER DISCUSSION
NWS TPC/NATIONAL HURRICANE CENTER MIAMI FL  
705 AM EST TUE JAN 04 2011

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.

...THE ITCZ...

ITCZ AXIS IS ANALYZED ALONG 6N8W 3N17W 4N33W 2N42W 1N52W. 
CLUSTERS OF SCATTERED MODERATE/ISOLATED STRONG CONVECTION ARE 
FROM 6N TO THE EQUATOR BETWEEN 10W-32W. 

...DISCUSSION...

GULF OF MEXICO...
THE UPPER LEVELS OF THE GULF ARE DOMINATED BY THE UPPER RIDGE 
THAT COVERS THE CARIBBEAN GIVING THE GULF SW TO W FLOW ALOFT. A 
SURFACE RIDGE COVERS THE GULF INTO THE W ATLC ANCHORED BY A 1025 
MB HIGH ALONG THE NORTH CAROLINA COAST GIVING THE GULF E TO SE 
SURFACE FLOW. BROKEN TO OVERCAST LOW LEVEL CLOUDS WITH POSSIBLE 
ISOLATED SHOWERS ARE N OF 25N W OF 94W AND W OF A LINE FROM S 
MEXICO NEAR 18N93W ALONG 22N96W TO 25N94W LEAVING THE REMAINDER 
OF THE S GULF UNDER CLEAR SKIES AGAIN THIS MORNING. 

CARIBBEAN SEA...
THE CARIBBEAN REMAINS RATHER TRANQUIL AGAIN THIS MORNING. THE 
UPPER LEVELS OF THE CARIBBEAN ARE DOMINATED BY A BROAD UPPER 
RIDGE ANCHORED OVER SOUTH AMERICA WITH MODERATE/STRONG 
SUBSIDENCE AND DRY STABLE AIR ALOFT. A SURFACE TROUGH IS OVER 
THE E CARIBBEAN EXTENDING FROM 17N65W 14N66W TO NEAR THE COAST 
OF SOUTH AMERICA NEAR 11N65W LEAVING THE AREA SE OF THE SURFACE 
TROUGH UNDER CLEAR SKIES THIS MORNING. BROKEN/OVERCAST LOW 
CLOUDS CONTINUE TO DRIFT W ACROSS THE CARIBBEAN SE OF A LINE 
FROM SW HAITI TO NE HONDURAS LEAVING THE NW CARIBBEAN UNDER 
CLEAR SKIES AS WELL THIS MORNING. 

ATLANTIC OCEAN...
A BROAD UPPER TROUGH IS MOVING OVER THE NW ATLC SUPPORTING A 
COLD FRONT THAT AT 04/0900 UTC ENTERS THE REGION NEAR 32N53W TO 
27N70W WHERE IT BEGINS TO DISSIPATE TO 26N74W CONTINUING TO 
DISSIPATE AS A STATIONARY FRONT ACROSS THE N BAHAMA ISLANDS TO 
NEAR 25N80W. DENSE LOW LEVEL CLOUDS WITH POSSIBLE ISOLATED 
SHOWERS WITHIN 60 NM SE OF THE COLD FRONT. THE BROAD UPPER RIDGE 
THAT COVERS THE CARIBBEAN ALSO COVERS THE W AND CENTRAL ATLC S 
OF 30N W OF 45W AND A SURFACE RIDGE ANCHORED BY A 1025 MB HIGH 
ALONG THE COAST OF NORTH CAROLINA IS BRIDGING THE ABOVE FRONT 
WITH A WEAK 1018 MB HIGH S OF THE FRONT NEAR 25N64W. AN UPPER 
TROUGH IS OVER THE CENTRAL/E ATLC SUPPORTING A COLD FRONT THAT 
EXTENDS ALONG 32N31W 25N40W TO 24N48W. AN UPPER RIDGE AXIS 
EXTENDS FROM AN UPPER HIGH IN THE TROPICS NEAR 8N25W TO BEYOND 
32N12W ENHANCING ISOLATED SHOWERS THAT DOT THE AREA WITHIN 150 
NM OF LINE FROM 13N36W TO 21N26W. WESTERLY FLOW ALOFT N OF THE 
ITCZ E OF 40W AND THE EASTERLY SURFACE LOW OVER THE SAME AREA 
ARE GENERATING SCATTERED SHOWERS AND POSSIBLE ISOLATED 
THUNDERSTORMS FROM 8N-12N BETWEEN 42W-53W. A WEAK SURFACE RIDGE 
REMAINS OVER THE FAR E ATLC AND W AFRICA. 

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

$$
PAW