000
AXNT20 KNHC 311730
TWDAT 

TROPICAL WEATHER DISCUSSION
NWS NATIONAL HURRICANE CENTER MIAMI FL
105 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 1200 UTC SURFACE ANALYSIS AND SATELLITE IMAGERY
THROUGH 1715 UTC.

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

MOST OF THE MONSOON TROUGH EXTENDS INLAND ACROSS AFRICA. A SMALL 
PORTION OF IT ENTERS THE ATLC WATERS THROUGH THE COAST OF SIERRA 
LEONE NEAR 8N13W QUICKLY ENDING AT 4N19W...WHERE THE ITCZ BEGINS 
AND CONTINUES WESTWARD ALONG 2N30W 3N41W TO THE COAST OF BRAZIL 
NEAR 1N50W. SCATTERED MODERATE CONVECTION IS WITHIN 130-170 NM 
ON EITHER SIDE OF THE ITCZ/MONSOON TROUGH E OF 30W. ISOLATED 
WEAK CONVECTION IS MOSTLY WITHIN 100 NM N OF THE ITCZ AXIS W OF 
30W. 

...DISCUSSION...

THE GULF OF MEXICO...
A FAIRLY STRONG HIGH PRESSURE SYSTEM ANCHORED IN THE WRN ATLC 
EXTENDS A SURFACE RIDGE AXIS SW INTO THE GULF...PROVIDING 
RELATIVELY FAIR WEATHER CONDITIONS WITH THE EXCEPTION OF A 
CLUSTER OF SCATTERED SHOWERS FROM 23N-27N BETWEEN 85W-88W. AN 
UPPER LEVEL LONGWAVE MOVES ACROSS NRN MEXICO AND SRN TEXAS 
ADVECTING MID TO UPPER LEVEL MOISTURE ACROSS THE NW AND N 
CENTRAL GULF. THIS FEATURE IS ALSO PROVIDING ENOUGH LIFTING TO 
GENERATE SCATTERED WEAK SHOWERS N OF 23N W OF 92W. A MODERATE 
PRESSURE GRADIENT IS GENERATING SE WINDS 15-20 KT ACROSS THE 
GULF...GUSTING TO 25 KT ACROSS THE STRAITS OF FLORIDA. A FEW 
REMNANT ISOLATED SHOWERS ARE IN THIS REGION AS WELL FROM THE 
PREVIOUS OLD BOUNDARY ANALYZED OVER THE PAST FEW DAYS. A WEAK 
SURFACE TROUGH IS ANALYZED OVER THE WRN BAY OF CAMPECHE WITH 
VERY LIMITED CONVECTION. 

THE CARIBBEAN SEA...
A MODERATE PRESSURE GRADIENT IS PRESENT ACROSS THE CARIBBEAN 
WATERS THIS AFTERNOON...GENERATING AN EASTERLY WIND FIELD OF 
15-20 KT ACROSS THE AREA. A RECENT SCAN FROM POLAR ORBITING 
SATELLITE DEPICTED THE STRONGEST WINDS ALONG THE COAST OF NRN 
COLOMBIA GUSTING TO 30 KT. A FEW ISOLATED SHOWERS ARE EMBEDDED 
IN THE OVERALL SURFACE FLOW...SUPPRESSED BY THE STRONG UPPER 
LEVEL RIDGE COVERING THE DISCUSSION AREA WITH DRY AIR AND STRONG 
SUBSIDENCE ALOFT. NO SIGNIFICANT CHANGES ARE EXPECTED DURING 
THE NEXT 24 HOURS. 

THE ATLANTIC OCEAN...
A FAIRLY STRONG 1032 MB HIGH IS MOVING OFF THE COASTAL WATERS OF 
THE CAROLINAS...KEEPING RELATIVELY FAIR WEATHER ACROSS THE AREA 
W OF A WEAKENING STATIONARY FRONT ANALYZED ALONG 32N55W SW TO 
THE CENTRAL BAHAMAS NEAR 24N78W. ISOLATED SHOWERS ARE WITHIN 50 
NM ON EITHER SIDE OF IT. THIS FEATURE HAS LOST MOST OF ITS UPPER 
LEVEL SUPPORT AND FURTHER WEAKENING IS EXPECTED OVER THE NEXT 24 
HOURS. A NARROW UPPER LEVEL RIDGE IS AHEAD OF THIS BOUNDARY 
SUPPORTING A STATIONARY 1027 MB HIGH NEAR 32N42W. AN UPPER LEVEL 
TROUGH MOVES ACROSS THE ERN ATLC DRAWING MID-UPPER LEVEL 
MOISTURE FROM THE ITCZ REGION TO WEST AFRICA.

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

$$

GARCIA