000
AXNT20 KNHC 192351
TWDAT 

TROPICAL WEATHER DISCUSSION
NWS NATIONAL HURRICANE CENTER MIAMI FL
705 PM EST THU JAN 19 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 
2315 UTC.

...ITCZ/MONSOON TROUGH...

THE MONSOON TROUGH EXTENDS FROM THE AFRICAN COAST NEAR 06N11W TO 
03N18W. THE INTERTROPICAL CONVERGENCE ZONE AXIS EXTENDS FROM 
03N18W TO 02N33W TO 03N44W TO 02N50W. ISOLATED MODERATE 
CONVECTION IS FROM THE EQUATOR TO 05N BETWEEN 23W-34W.

...DISCUSSION...

GULF OF MEXICO...
WATER VAPOR IMAGERY INDICATES THAT NORTHWESTERLY UPPER LEVEL 
FLOW IS DOMINANT ALOFT ACROSS THE GULF THIS EVENING AS A COLD 
FRONT CONTINUES TO SLIDE E-SE OVER THE SE GULF. THE FRONT 
CONTINUES TO EXIT THE REGION AND IS ANALYZED FROM 24N80W TO 
23N84W BECOMING A DISSIPATING STATIONARY BOUNDARY TO 24N90W. 
VERY LITTLE LOW-LEVEL MOISTURE REMAINS IN THE VICINITY OF THE 
FRONT AS A HIGH PRESSURE RIDGE CONTINUES TO HOLD STRONG FROM 
NORTHERN FLORIDA SOUTHWESTWARD TO EAST-CENTRAL MEXICO NEAR 
23N98W. SOUTHERLY RETURN FLOW...NOTED ON SHIP...BUOY...AND 
OFFSHORE OIL PLATFORMS THIS EVENING...IS LOCATED NORTH OF THE 
RIDGE AXIS AND IS EXPECTED TO PERSIST THROUGH THE UPCOMING 
WEEKEND UNTIL LATE SUNDAY INTO EARLY MONDAY WHEN THE NEXT COLD 
FRONT EMERGES OFF THE TEXAS COAST INTO THE NW GULF WATERS.

CARIBBEAN SEA...
NORTHWESTERLY UPPER LEVEL FLOW IS OVER THE CARIBBEAN BASIN THIS 
EVENING WHICH IS PROVIDING AN OVERALL DRY AND STABLE ATMOSPHERE 
ALOFT LIMITING ANY SIGNIFICANT AREAS OF DEEP CONVECTION. FRESH 
TO STRONG EASTERLY TRADES ARE FORECAST TO PERSIST THROUGH THE 
UPCOMING WEEKEND WITH NO MAJOR CHANGES EXPECTED TO MODIFY THE 
CURRENT WEATHER PATTERN.

ATLANTIC OCEAN...
AN UPPER LEVEL TROUGH IS OVER THE WESTERN NORTH ATLC WATERS WITH 
AXIS EXTENDING MOSTLY ALONG 66W N OF 32N THEN FROM 32N66W TO 
26N70W. THIS TROUGH SUPPORTS A COLD FRONT ANALYZED FROM 32N67W 
TO THE NW BAHAMAS NEAR 26N77W ACROSS THE FLORIDA STRAITS AND 
INTO THE SE GULF OF MEXICO. LOW-LEVEL MOISTURE REMAINS LIMITED 
WITH THIS FRONT AS ONLY A FEW ISOLATED SHOWERS ARE OCCURRING 
WITHIN 60 NM EITHER SIDE OF THE FRONT N OF 27N. ISOLATED SHOWERS 
AND TSTMS ARE ALSO WITHIN THE FRONTAL TROUGHING N OF 20N BETWEEN 
58W-72W. EAST OF THE INFLUENCE OF THE COLD FRONT AND SUPPORTING 
UPPER LEVEL TROUGH...A SHARP UPPER LEVEL RIDGE WITH AXIS FROM 
32N54W TO 22N60W IS SUPPORTIVE OF A SURFACE RIDGE ANCHORED BY A 
1031 MB HIGH CENTERED NEAR 37N41W. AN UPPER LEVEL LOW IS OVER 
THE CENTRAL ATLC CENTERED NEAR 29N47W WITH A TROUGH AXIS 
EXTENDING FROM THE LOW SOUTHWARD TO 18N50W. THE TROUGH SUPPORTS 
A STATIONARY FRONT ANALYZED FROM 32N34W TO 19N46W WITH SCATTERED 
SHOWERS AND TSTMS OCCURRING WITHIN 240 NM EITHER SIDE OF THE 
BOUNDARY. THE REMAINDER OF THE EASTERN ATLC IS UNDER THE 
INFLUENCE OF A SURFACE RIDGE ANCHORED BY A 1041 MB HIGH CENTERED 
WEST OF THE IBERIAN PENINSULA NEAR 42N14W.

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

$$
HUFFMAN