000
AXNT20 KNHC 071136
TWDAT 

TROPICAL WEATHER DISCUSSION
NWS NATIONAL HURRICANE CENTER MIAMI FL
705 AM EST WED MAR 07 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 0600 UTC SURFACE ANALYSIS AND SATELLITE IMAGERY THROUGH 
1115 UTC.

...ITCZ/MONSOON TROUGH...

THE MONSOON TROUGH EXTENDS ACROSS W AFRICA TO THE COAST OF 
SIERRA LEONE AT 8N13W TO 5N19W. THE ITCZ CONTINUES FROM 5N19W 
ALONG 3N30W 2N40W 1S49W. SCATTERED MODERATE CONVECTION IS FROM 
2N-4N BETWEEN 45W-51W.    

...DISCUSSION...

GULF OF MEXICO...
UPPER LEVEL RIDGING COVERS THE GULF OF MEXICO THIS MORNING WITH 
AXIS EXTENDING FROM THE E PACIFIC ACROSS THE BAY OF CAMPECHE TO 
THE ERN CONUS. THE UPPER RIDGE IS SUPPORTING A STRONG SURFACE 
RIDGE ANCHORED BY A 1038 MB HIGH E OF NORTH CAROLINA NEAR 
36N72W. THIS PATTERN IS PROVIDING STRONG E-SE FLOW ACROSS THE 
GULF RANGING FROM 15-25 KTS. DRY AIR ALOFT IS KEEPING SKIES 
MOSTLY CLEAR BESIDES SOME LOW-LEVEL CLOUD COVER AND ISOLATED 
SHOWERS ACROSS THE SE GULF AND ALONG THE COAST OF MEXICO. THE 
SURFACE RIDGE IS EXPECTED TO SHIFT EWD OVER THE NEXT COUPLE OF 
DAYS...BUT STRONG E-SE FLOW WILL REMAIN ACROSS THE 
BASIN...ESPECIALLY THE ERN HALF. 

CARIBBEAN SEA...
A NEARLY DISSIPATED SHEARLINE CONTINUES TO SIT OVER THE NW 
CARIBBEAN EXTENDING FROM ERN CUBA NEAR 20N75W TO 17N86W. 
ISOLATED SHOWERS ARE WITHIN 90 NM S OF THE AXIS AND WITHIN 200 
NM N OF THE AXIS. THE SHEARLINE IS THE REMNANT OF A FRONTAL 
BOUNDARY THAT IS IN THE W ATLC. THE SYSTEM IS SUPPORTED BY AN 
UPPER LEVEL TROUGH WHICH EXTENDS FROM THE W ATLC ACROSS CUBA TO 
THE SW CARIBBEAN ALONG 78W. THE ERN CARIBBEAN IS COVERED BY AN 
UPPER LEVEL RIDGE ALONG 67W. DRY AIR ALOFT IS OVER THE MAJORITY 
OF THE BASIN PROVIDING FAIR CONDITIONS AND CLEAR SKIES BESIDES 
THE AREA NOTED IN THE NW CORNER. TRADEWIND FLOW OF 20-25 KTS IS 
ACROSS MUCH OF THE BASIN REACHING GALE FORCE NEAR THE COAST OF 
COLOMBIA. A FEW LOW LEVEL CLOUDS WITH POSSIBLE ISOLATED SHOWERS 
ARE EMBEDDED WITHIN THE TRADEWIND FLOW. EXPECT THE SHEAR AXIS TO 
CONTINUE TO DISSIPATE WITH LITTLE CHANGE ELSEWHERE. 

ATLANTIC OCEAN...
A STRONG SURFACE RIDGE IS BUILDING ACROSS THE W ATLC AROUND A 
1038 MB HIGH E OF NORTH CAROLINA NEAR 36N72W. AN UPPER LEVEL 
TROUGH IS OVER THE W ATLC ALONG 71W CONTINUING INTO THE ERN 
CARIBBEAN SUPPORTING A WEAKENING FRONTAL SYSTEM THAT EXTENDS 
INTO THE SURFACE RIDGE. THE SYSTEM CONSISTS OF A WEAKENING COLD 
FRONT ENTERING THE DISCUSSION AREA AT 31N54W TO 27N61W WHERE IT 
TRANSITIONS INTO A SHEARLINE TO THE FLORIDA KEYS ALONG 25N70W 
25N81W. ISOLATED SHOWERS ARE WITHIN 120 NM AHEAD OF THE AXIS E 
OF 62W...AND WITHIN 120 N OF THE AXIS W OF 62W. A PATCH OF 
THUNDERSTORMS IS ALSO FROM 25N-26N BETWEEN 71W-72W. AN UPPER 
LEVEL RIDGE COVERS THE CENTRAL ATLC EXTENDING FROM THE NE 
CARIBBEAN TO NEAR 35N43W. AN UPPER LEVEL LOW IS FARTHER E NEAR 
30N35W SUPPORTING A SURFACE TROUGH ALONG 31N36W TO 25N37W. 
SCATTERED SHOWERS ARE WITHIN 230 NM E OF THE AXIS. THE UPPER 
TROUGH AXIS CONNECTED TO THE UPPER LOW EXTENDS TOWARDS THE SW TO 
14N53W. A BROAD UPPER RIDGE COVERS THE TROPICAL ATLC CENTERED 
NEAR 4N25W. A STREAM OF UPPER LEVEL CLOUDS EXTENDS FROM THE NE 
COAST OF SOUTH AMERICA TO NW AFRICA IN THE AREA OF AN UPPER 
LEVEL JET BETWEEN THE UPPER TROUGH E OF THE WINDWARD ISLANDS AND 
THE UPPER RIDGE OVER THE TROPICAL ATLC. 

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

$$
WALTON