000
AXNT20 KNHC 121755
TWDAT 

TROPICAL WEATHER DISCUSSION
NWS TPC/NATIONAL HURRICANE CENTER MIAMI FL  
105 PM EST TUE JAN 12 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 1200 UTC SURFACE ANALYSIS AND SATELLITE IMAGERY
THROUGH 1715 UTC.

...THE ITCZ...

FROM NORTHERN COASTAL SIERRA LEONE TO 5N20W 3N30W...CROSSING
THE ITCZ ALONG 40W...INTO NORTHEASTERN BRAZIL NEAR 2S49W.
SHOWERS ARE POSSIBLE OVER THE WATERS TO THE SOUTH OF 5N
TO THE EAST OF 51W.

...DISCUSSION...

THE GULF OF MEXICO...
A NORTHEAST-TO-SOUTHWEST ORIENTED MIDDLE LEVEL TO UPPER LEVEL 
TROUGH PASSES THROUGH NORTH CAROLINA TO NORTHERN GEORGIA TO
CENTRAL LOUISIANA. CYCLONIC FLOW AROUND THIS TROUGH COVERS THE 
GULF OF MEXICO TO THE NORTH OF 28N. MOIST UPPER LEVEL 
SOUTHWESTERLY WIND FLOW MOVES FROM THE EASTERN PACIFIC OCEAN 
NEAR 11N108W TO THE SOUTHWESTERN MEXICO COAST BETWEEN THE GULF 
OF TEHUANTEPEC AND 20N106W...IT CROSSES MEXICO...AND IT ENTERS 
THE GULF OF MEXICO EASILY REACHING 90W. PARTS OF THE UPPER LEVEL 
MOISTURE BRUSH THE NORTHERN YUCATAN PENINSULA AND HEAD INTO THE 
STRAITS OF FLORIDA. A MIDDLE LEVEL TO UPPER LEVEL CYCLONIC 
CIRCULATION CENTER CONTINUES IN NORTH CENTRAL MEXICO NEAR 
27N104W. CYCLONIC FLOW AROUND THIS CENTER COVERS THE AREA FROM
25N TO 31N BETWEEN 99W AND 107W. BROAD SURFACE ANTICYCLONIC WIND
FLOW COVERS THE GULF OF MEXICO. THE SURFACE PRESSURE GRADIENT 
STILL IS SIGNIFICANT ENOUGH FROM TEXAS TO SOUTH CENTRAL MEXICO 
IN ORDER TO BE GENERATING GALE-FORCE WINDS IN THE GULF OF 
TEHUANTEPEC ON THE PACIFIC OCEAN SIDE OF MEXICO. 

THE CARIBBEAN SEA...
A REMNANT CLOUD LINE/SHEAR AXIS FROM AN OLD FRONTAL BOUNDARY 
EXTENDS FROM THE SOUTHWESTERN COAST OF THE DOMINICAN REPUBLIC
TO 15N77W 12N80W TO PANAMA NEAR 8N82W. BROKEN TO OVERCAST
STRATIFORM CLOUDS COVER THE THE CARIBBEAN SEA TO THE NORTHWEST 
AND WEST OF THE LINE REMNANT CLOUD LINE/SHEAR AXIS.
BROAD UPPER LEVEL ANTICYCLONIC FLOW COVERS THE AREA IN GENERAL. 
AN UPPER LEVEL INVERTED TROUGH IS IN COLOMBIA TO THE SOUTH OF 
10N ALONG 74W/75W. A LOW LEVEL TROUGH IS IN THE SOUTHEASTERN 
CORNER OF THE AREA ALONG 16N62W 11N63W.

THE ATLANTIC OCEAN...
UPPER LEVEL SOUTHWESTERLY WIND FLOW IS TO THE WEST OF THE LINE 
THAT PASSES THROUGH 32N47W 24N60W BEYOND THE WINDWARD PASSAGE.
NO MORE CYCLONIC FLOW REMAINS TO THE SOUTH OF 32N TO THE WEST
OF THE 32N47W-WINDWARD PASSAGE LINE IN ORDER TO SUPPORT THE 
UPPER LEVELS OF THE ATMOSPHERE THAT ARE ON TOP OF THE CURRENT
CENTRAL ATLANTIC OCEAN FRONTAL BOUNDARY. THE FRONT IS COLD
THROUGH 32N48W TO 24N55W...DISSIPATING COLD FROM 24N55W TO 
20N62W TO THE SOUTHWESTERN COAST OF THE DOMINICAN REPUBLIC.
LITTLE TO NO PRECIPITATION IS EVIDENT WITH THIS FRONT.
SURFACE ANTICYCLONIC WIND FLOW MOVES AROUND A RIDGE THAT
EXTENDS FROM A 1028 MB HIGH PRESSURE CENTER THAT IS NEAR
29N15W TO 25N35W 23N45W 24N51W. AN UPPER LEVEL TROUGH/
SHEAR AXIS IS ALONG 19N20W 17N30W 10N34W 5N37W 4N50W.

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

$$
MT