000
AXNT20 KNHC 172348
TWDAT 

TROPICAL WEATHER DISCUSSION
NWS NATIONAL HURRICANE CENTER MIAMI FL
705 PM EST TUE JAN 17 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 09N13W TO 
04N22W. THE INTERTROPICAL CONVERGENCE ZONE AXIS EXTENDS FROM 
04N22W TO 03N40W TO 02N51W. NO SIGNIFICANT CONVECTION IS NOTED 
ON SATELLITE IMAGERY.   

...DISCUSSION...

GULF OF MEXICO...
A BROAD UPPER LEVEL RIDGE IS LOCATED OVER THE GULF WITH AXIS 
EXTENDING ALONG 93W. THIS UPPER LEVEL FEATURE SUPPORTS A SURFACE 
RIDGE THAT EXTENDS FROM THE SW NORTH ATLC...ACROSS THE FLORIDA 
PENINSULA TO EAST-CENTRAL MEXICO NEAR 23N98W. MOST OF THE GULF 
IS UNDER SOUTH-SOUTHWESTERLY WINDS AHEAD OF A COLD FRONT THAT IS 
ANALYZED ACROSS SE TEXAS AND IS EXPECTED TO EMERGE OFF THE COAST 
WITHIN THE NEXT 3 TO 6 HOURS. OTHERWISE...CLEAR SKIES AND FAIR 
WEATHER PREVAILS ELSEWHERE THIS EVENING. THE APPROACHING COLD 
FRONT IS FORECAST TO BRING STRONG N-NE WINDS THROUGH LATE 
WEDNESDAY AS HIGH PRESSURE WILL BUILD BACK IN BEHIND THE FRONT.

CARIBBEAN SEA...
THE CARIBBEAN BASIN IS UNDER THE INFLUENCE OF UPPER LEVEL 
WESTERLY FLOW WITH WATER VAPOR IMAGERY INDICATING A VERY DRY AND 
STABLE ATMOSPHERE ALOFT THIS EVENING. HOWEVER...WITH A STRONG 
HIGH PRESSURE SYSTEM LOCATED OVER THE SW NORTH ATLC AND LOWER 
PRESSURE ACROSS NORTHERN SOUTH AMERICA...A RELATIVELY STRONG 
PRESSURE GRADIENT IS SET UP ACROSS THE BASIN PROVIDING STRONG 
TRADES IN THE RANGE OF 15 TO 25 KT...WITH GALE FORCE CONDITIONS 
OCCURRING FROM 10N TO 12N BETWEEN 75W AND 77W NEAR THE COAST OF 
COLOMBIA. THESE CONDITIONS ARE EXPECTED TO PERSIST OVER THE NEXT 
24 HOURS AS THE WESTERN ATLC HIGH SHIFTS EAST THROUGH EARLY 
THURSDAY. AREAS OF LOW-LEVEL CLOUDS AND POSSIBLE EMBEDDED 
ISOLATED SHOWERS ARE OVER MUCH OF THE AREA WITHIN THE E-NE 
TRADEWIND FLOW.

ATLANTIC OCEAN...
AN UPPER LEVEL RIDGE IS OVER THE WESTERN ATLC WITH AXIS 
EXTENDING ALONG THE EASTERN U.S. SEABOARD. THIS UPPER LEVEL 
FEATURE SUPPORTS A 1032 MB HIGH CENTERED IN THE VICINITY OF 
BERMUDA NEAR 32N63W THAT ENCOMPASSES MUCH OF THE SW NORTH ATLC N 
OF 22N W OF 55W WITH MOSTLY FAIR CONDITIONS OBSERVED THIS 
EVENING. FARTHER EAST...AN UPPER LEVEL TROUGH IS OVER THE 
CENTRAL ATLC WITH AXIS ALONG 36N46W TO 30N51W TO 21N67W THAT 
SUPPORTS A COLD FRONT ANALYZED FROM 32N41W TO 23N50W TO EASTERN 
HISPANIOLA NEAR 19N68W. WIDELY SCATTERED SHOWERS AND ISOLATED 
TSTMS ARE OCCURRING WITHIN 180 NM EAST OF THE FRONT N OF 23N. 
ELSEWHERE ISOLATED SHOWERS ARE OCCURRING WITHIN 120 NM EITHER 
SIDE OF THE FRONT S OF 23N. THE REMAINDER OF THE EASTERN ATLC IS 
UNDER THE INFLUENCE OF A SURFACE RIDGE ANCHORED BY A 1032 MB 
HIGH CENTERED NEAR 39N17W.

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

$$
HUFFMAN