000
AXNT20 KNHC 312340
TWDAT 

TROPICAL WEATHER DISCUSSION
NWS NATIONAL HURRICANE CENTER MIAMI FL
705 PM EST TUE JAN 31 2012

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...WEATHER OBSERVATIONS...RADAR...AND
METEOROLOGICAL ANALYSIS.

BASED ON 1800 UTC SURFACE ANALYSIS AND SATELLITE IMAGERY
THROUGH 2300 UTC.

...THE ITCZ/THE MONSOON TROUGH...

THE MONSOON TROUGH EXTENDS ACROSS W AFRICA TO THE SRN COAST OF 
GUINEA AT 10N14W TO 5N21W. THE ITCZ CONTINUES FROM 5N21W ALONG 
2N35W 3N43W 1N51W. ISOLATED MODERATE/STRONG CONVECTION IS WITHIN 
150 NM S OF THE AXIS BETWEEN 19W-29W...AND WITHIN 80 NM N OF THE 
AXIS BETWEEN 45W-50W. 

...DISCUSSION...

THE GULF OF MEXICO...
SURFACE RIDGING EXTENDING FROM A 1031 MB HIGH OVER THE W ATLC 
CONTINUES TO SIT OVER THE GULF OF MEXICO WITH ANTI-CYCLONIC 
SURFACE FLOW OF 10-15 KTS WITH AN AREA OF 20 KT WINDS THROUGH 
THE FLORIDA STRAITS AND SE GULF. DESPITE THE RIDGING...ABUNDANT 
MOISTURE IS ACROSS MUCH OF THE BASIN BESIDES THE FAR ERN GULF E 
OF 85W. WATER VAPOR IMAGERY INDICATES UPPER LEVEL MOISTURE IS 
BEING DRAWN FROM THE E PACIFIC IN SWLY FLOW AROUND AN UPPER 
LEVEL RIDGE OVER THE CARIBBEAN SUPPORTING OVERCAST SKIES. 
ISOLATED SHOWERS ARE ALSO EVIDENT IN RADAR IMAGERY ACROSS THE NW 
GULF. A SURFACE TROUGH IS NOTED IN THE FAR SW CARIBBEAN ALONG 
23N95W TO 16N92W. A LINE OF SHOWERS IS ALONG THE AXIS WITH AN 
AREA OF SCATTERED SHOWERS/THUNDERSTORMS TO THE N FROM 24N-27N 
BETWEEN 93W-96W. EXPECT THE SURFACE TROUGH TO DRIFT WWD AND 
DISSIPATE OVER MEXICO WHILE SURFACE RIDGING CONTINUES TO 
DOMINATE THE REMAINDER OF THE BASIN. MOIST CONDITIONS WILL ALSO 
REMAIN OVER THE WRN HALF OF THE GULF ESPECIALLY THE NW CORNER. 

THE CARIBBEAN SEA...
A MODERATE PRESSURE GRADIENT HAS BUILT UP OVER THE CARIBBEAN SEA
BETWEEN LOWER PRESSURE OVER S AMERICA AND HIGH PRESSURE OVER THE 
W ATLC. THIS GRADIENT IS SUPPORTING 20-25 KT TRADEWIND FLOW 
ACROSS THE MAJORITY OF THE BASIN...INCREASING TO GALE FORCE  
NEAR THE COAST OF COLOMBIA. BESIDES THE STRONG WINDS...DRY AIR 
ALOFT AROUND AN UPPER LEVEL RIDGE CENTERED OVER VENEZUELA IS 
MAINTAINING MOSTLY FAIR WEATHER. SOME UPPER LEVEL MOISTURE IS 
PRESENT OVER THE NW CORNER OF THE ARE SUPPORTING HIGH CLOUDS. 
PATCHES OF CLOUDS AND POSSIBLE ISOLATED SHOWERS ARE ALSO 
EMBEDDED WITHIN THE TRADEWIND FLOW. EXPECT GALE FORCE WINDS TO 
CONTINUE NEAR THE COAST OF COLOMBIA WITH LITTLE CHANGE ELSEWHERE 
OVER THE NEXT 24 HOURS. 

THE ATLANTIC OCEAN...
AN UPPER LEVEL RIDGE COVERING THE GULF OF 
MEXICO...CARIBBEAN...AND W ATLC ALONG 76W SUPPORTS A 1031 MB 
SURFACE HIGH NEAR 33N73W WHICH IS PROVIDING MOSTLY FAIR WEATHER 
ACROSS THE W ATLC. HOWEVER...A STATIONARY BOUNDARY EXTENDS 
THROUGH THE RIDGE ALONG 31N57W 26N70W DISSIPATING TO THE BAHAMAS 
NEAR 24N77W. ISOLATED SHOWERS ARE WITHIN 30 NM EITHER SIDE OF 
THE AXIS. THE FRONT IS LOSING ITS STRENGTH AS THE BROAD UPPER 
TROUGH SUPPORTING IT IS NOW MOVING INTO THE CENTRAL ATLC AND TO 
THE N OF 29N. THE FRONT WILL LIKELY BEGIN TO DISSIPATE. TO THE 
E...A NARROW UPPER LEVEL RIDGE EXTENDS ALONG 21N55W TO THE 
AZORES ISLANDS NEAR 38N27W SUPPORTING A 1025 MB HIGH NEAR 30N47W 
AND A SECOND HIGH CENTER NEAR THE AZORES. AN UPPER LEVEL TROUGH 
COVERS THE FAR ERN ATLC FROM THE CANARY ISLANDS TO NEAR 8N49W. 
THE UPPER TROUGH IS ENHANCING UPPER LEVEL CLOUDS FROM THE ITCZ 
REGION TO W AFRICA. 

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

$$
WALTON