000 AXNT20 KNHC 070544 TWDAT TROPICAL WEATHER DISCUSSION NWS NATIONAL HURRICANE CENTER MIAMI FL 105 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 0000 UTC SURFACE ANALYSIS AND SATELLITE IMAGERY THROUGH 0515 UTC. ...ITCZ/MONSOON TROUGH... THE MONSOON TROUGH EXTENDS S OF W AFRICA FROM THE PRIME MERIDIAN AND 4N ALONG 3N12W 2N27W. THE ITCZ CONTINUES FROM 2N27W ALONG 3N37W TO THE COAST OF BRAZIL NEAR 1S47W. ISOLATED MODERATE CONVECTION IS WITHIN 100 NM N OF THE AXIS BETWEEN 36W-45W. ...DISCUSSION... GULF OF MEXICO... UPPER LEVEL RIDGING COVERS THE GULF OF MEXICO TONIGHT 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 VIRGINIA NEAR 38N72W. THIS PATTERN IS PROVIDING STRONG NE-E FLOW ACROSS THE GULF RANGING FROM 15-25 KTS. DRY AIR ALOFT IS KEEPING SKIES MOSTLY CLEAR BESIDES SOME LOW-LEVEL CLOUD COVER ACROSS THE FLORIDA STRAITS AND ALONG THE COAST OF MEXICO. THE SURFACE RIDGE IS EXPECTED TO SHIFT EWD OVER THE NEXT COUPLE OF DAYS...BUT STRONG NE-E FLOW WILL REMAIN ACROSS THE BASIN. CARIBBEAN SEA... AS OF 0300 UTC...A SHEAR AXIS EXTENDS FROM ERN CUBA NEAR 21N77W TO 19N86W. A CLUSTER OF SHOWERS/THUNDERSTORMS IS S OF THE AXIS FROM 19N-21N BETWEEN 76W-80W. POSSIBLE ISOLATED SHOWERS ARE ACROSS THE REMAINDER OF THE NW CARIBBEAN 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 80W. THE ERN CARIBBEAN IS COVERED BY AN UPPER LEVEL RIDGE ALONG 70W. 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. EXPECT THE SHEAR AXIS TO GRADUALLY DISSIPATE WITH LITTLE CHANGE ELSEWHERE. ATLANTIC OCEAN... A STRONG SURFACE RIDGE IS BUILDING ACROSS THE W ATLC AROUND A 1038 MB HIGH E OF VIRGINIA NEAR 38N72W. AN UPPER LEVEL TROUGH IS OVER THE W ATLC ALONG 74W CONTINUING INTO THE ERN CARIBBEAN SUPPORTING A WEAKENING FRONTAL SYSTEM THAT EXTENDS INTO THE SRN EXTENT OF THE SURFACE RIDGE. THE SYSTEM CONSISTS OF A WEAKENING COLD FRONT ENTERING THE DISCUSSION AREA AT 32N58W EXTENDING TO THE FLORIDA STRAITS ALONG 27N68W 25N82W. ISOLATED SHOWERS ARE WITHIN 60 NM EITHER SIDE THE AXIS. A SURFACE TROUGH IS AHEAD OF THE FRONT ALONG 32N55W TO 23N72W WHERE IT TRANSITIONS INTO A SHEAR AXIS TO ERN CUBA NEAR 21N77W. ISOLATED SHOWERS ARE ALONG THE AXIS. AN UPPER LEVEL RIDGE COVERS THE CENTRAL ATLC EXTENDING FROM THE NE CARIBBEAN TO NEAR 35N44W SUPPORTING A 1028 MB HIGH NEAR 30N53W. AN UPPER LEVEL LOW IS FARTHER E NEAR 30N34W SUPPORTING A 1019 MB SURFACE LOW. SCATTERED SHOWERS ARE WITHIN 90 NM OF THE LOW CENTER. THE UPPER TROUGH AXIS CONNECTED TO THE UPPER LOW EXTENDS TOWARDS THE SW TO E OF THE WINDWARD ISLANDS. A BROAD UPPER RIDGE COVERS THE TROPICAL ATLC CENTERED NEAR 5N24W. A STREAM OF UPPER LEVEL CLOUDS EXTENDS FROM THE NE COAST OF SOUTH AMERICA TO W 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