000 AXNT20 KNHC 062354 TWDAT TROPICAL WEATHER DISCUSSION NWS NATIONAL HURRICANE CENTER MIAMI FL 705 PM EST TUE MAR 06 2012 CORRECTED FOR PRECIPITATION INFORMATION IN NORTHWESTERN COLOMBIA NEAR THE PANAMA BORDER...AND FOR THE ATLANTIC OCEAN SECTION 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. ...THE ITCZ/THE MONSOON TROUGH... THE MONSOON TROUGH EXTENDS SW FROM THE AFRICAN COAST AT 11N15W TO 04N22W WHERE LOW LEVEL WINDS INDICATE A TRANSITION TO AN ITCZ WHICH CONTINUES SW THROUGH 00N37W TO THE COAST OF S AMERICA AT 02S43W. ISOLATED MODERATE CONVECTION IS NOTED S OF 07N TO THE EQUATOR E OF 14W. LOCALLY BROKEN LOW AND MID LEVEL CLOUDS WITH EMBEDDED SHOWERS ARE OBSERVED WITHIN 120 NM EITHER SIDE OF A LINE FROM 03N17W TO 00N27W TO 04N33W TO 04N37W. ...DISCUSSION... THE GULF OF MEXICO... AN UPPER LEVEL TROUGH EXTENDS S ACROSS THE EASTERN GULF OF MEXICO WHILE AN UPPER RIDGE IS BUILDING N ACROSS THE WESTERN GULF. THE UPPER TROUGH IS ACCOMPANIED BY VERY DRY AIR ALOFT AND IS SUPPRESSING CLOUDINESS AND CONVECTION OVER THE NE GULF...N OF 26N E OF 85W. AN UPPER LEVEL MOISTURE PLUME ORIGINATING IN THE PACIFIC IS STREAMING NE ACROSS NORTHERN MEXICO...TURNING E ACROSS THE UPPER RIDGE WITH THE MOISTURE THEN FANNING OUT OVER TEXAS AND LOUISIANA...WITH THIN CIRRUS NOW STREAMING E ACROSS THE EXTREME NW GULF. AT THE LOW LEVELS A RIDGE DISSECTS THE GULF FROM N FLORIDA TO THE BAY OF CAMPECHE. LOW LEVEL CLOUDS ASSOCIATED WITH A FRONTAL TROUGH ARE MOVING N OVER THE SE GULF. LOCALLY OVERCAST LOW LEVEL CLOUDS...LIKELY WITH EMBEDDED SHOWERS...ARE WITHIN 100 NM OF THE MEXICAN COAST FROM THE BAY OF CAMPECHE AT 18N94W TO NEAR 24.5N98W...AND ARE ALSO MOVING SLOWLY N WITH TIME. AN PATCH OF FAIR-WEATHER STRATOCUMULUS CLOUDS IS OBSERVED OVER THE CENTRAL GULF AND ALSO MOVING SLOWLY NW. THE CARIBBEAN SEA... AN UPPER TROUGH IS AMPLIFYING SE OVER THE NW CARIBBEAN AND IS ACCOMPANIED BY VERY DRY AIR ALOFT. A COUPLE OF COLD FRONTS HAVE WEAKENED TO SHEAR LINES EXTENDING E TO W ACROSS THE N-CENTRAL AND NW CARIBBEAN...AND ARE ACCOMPANIED BY LOCALLY BROKEN LOW AND MID LEVELS CLOUDS THAT ARE MOVING WESTWARD IN THE FAIRLY STRONG NE LOW LEVEL FLOW. ONE SHEAR LINE EXTENDS FROM HISPANIOLA TO JAMAICA TO THE E GULF OF HONDURAS WHILE A SECOND SHEAR LINE EXTENDS ACROSS CENTRAL CUBA TO THE YUCATAN PENINSULA. THE DRY AIR ALOFT IS SUPPRESSING ASSOCIATED CONVECTION TO EMBEDDED LIGHT SHOWERS. THE REMAINDER OF THE CARIBBEAN IS DOMINATED BY AN UPPER RIDGE ALOFT WITH STRONG WESTERLIES. TRADE WIND CUMULUS IS OBSERVED RACING W ACROSS THE NE CARIBBEAN. THE TRADES ARE ENHANCED ALONG THE NW COAST OF COLOMBIA WITH A 30 TO 35 KT GALE WARNING IN EFFECT FROM 11N TO 13N BETWEEN 73W AND 79W AND EXPECTED TO PERSIST THROUGH THU BUT SPREAD N TO ALONG 15N WITH SEAS BUILDING TO 19 FT. THE ATLANTIC OCEAN... AN UPPER TROUGH IS MOVING OFF THE EASTERN SEABOARD OF THE CONUS AND EXTENDS S OVER THE NW BAHAMAS AND IS ACCOMPANIED BY VERY DRY UPPER AIR. A UPPER RIDGE DISSECTS THE CENTRAL ATLANTIC AND EXTENDS NE FROM THE CARIBBEAN TO AN UPPER ANTICYCLONE AT 35N46W. A NARROW BAND OF UPPER MOISTURE IS STREAMING NE ALONG THE NW PERIPHERY OF THIS RIDGE...ROUGHLY WITHIN 75 NM EITHER SIDE OF A LINE FROM 24N75W TO BEYOND 32N57W. IMMEDIATELY TO THE SE OF THIS RIDGE...IS AN UPPER TROUGH THAT DOMINATES THE UPPER LEVELS OF THE EASTERN ATLANTIC...AND EXTENDS SW THROUGH THREE LARGE UPPER CYCLONES. THE EASTERNMOST DEEP LAYERED CYCLONE IS LOCATED OVER NORTHERN AFRICA...ANOTHER DEEP LAYERED CYCLONE IS OVER THE CENTRAL ATLANTIC AND ANALYZED AS 1023 MB AT THE SURFACE AT 30N32W...AND THE SOUTHERNMOST CYCLONE IS ALOFT AT 15N53W WITH THE UPPER TROUGH CONTINUING SW TO BASE OVER THE DEEP TROPICS AT 08N59W. CLOUDINESS AND CONVECTION IS ENHANCED WITHIN 360 NM OVER THE NE AND WITHIN 90 NM OVER THE SW SEMICIRCLES OF THE CENTRAL ATLANTIC CYCLONE. ASSOCIATED UPPER MOISTURE EXTENDS NE FROM THE THIS CONVECTION TO OVER THE CANARY ISLANDS. A BROAD UPPER RIDGE DOMINATES THE SE PORTION OF THE N ATLANTIC WITH A VERY DENSE MOISTURE PLUME...ORIGINATING OVER S AMERICA...STREAMING NE ALONG THE NW PERIPHERY OF RIDGE...ALL WITHIN 480 NM EITHER SIDE OF A LINE FROM 01N50W TO 14N35W TO ACROSS AFRICA AT 18N16W. AT THE LOW LEVELS...TWO COLDS FRONTS ARE WEAKENING FROM NEAR 32N60W TO ACROSS THE SE AND NW BAHAMAS RESULTING IN A BROAD AREA OF LOCALLY OVERCAST LOW AND MID LEVELS CLOUDS AND EMBEDDED SHOWERS. TO THE NW OF FRONTAL CLOUDINESS...LOCALLY BROKEN COLD AIR STRATOCUMULUS CLOUDS ARE OBSERVED TO THE E COAST OF THE CONUS. FOR ADDITIONAL INFORMATION PLEASE VISIT HTTP://WWW.HURRICANES.GOV/MARINE $$ NELSON