000 AXNT20 KNHC 270538 TWDAT TROPICAL WEATHER DISCUSSION NWS NATIONAL HURRICANE CENTER MIAMI FL 205 AM EDT SUN MAR 27 2011 TROPICAL WEATHER DISCUSSION FOR NORTH AMERICA...CENTRAL AMERICA...GULF OF MEXICO...CARIBBEAN SEA...NORTHERN SECTION OF SOUTH AMERICA...AND ATLANTIC OCEAN TO THE AFRICAN COAST FROM THE EQUATOR TO 32N. THE FOLLOWING INFORMATION IS BASED ON SATELLITE IMAGERY...METEOROLOGICAL ANALYSIS...WEATHER OBSERVATIONS...AND RADAR. BASED ON 0000 UTC SURFACE ANALYSIS AND SATELLITE IMAGERY THROUGH 0515 UTC. ...ITCZ... ITCZ AXIS IS ANALYZED ALONG 7N12W 5N16W 3N26W CROSSING THE EQUATOR NEAR 34W CONTINUING SOUTH OF THE EQUATOR TO INLAND OVER SOUTH AMERICA. CLUSTERS OF SCATTERED MODERATE/ISOLATED STRONG CONVECTION ARE WITHIN 75 NM OF LINE FROM 3N28W 2N37W TO S OF THE EQUATOR NEAR 43W. ...DISCUSSION... GULF OF MEXICO... BROAD UPPER RIDGE ANCHORED IN THE E PACIFIC REGION EXTENDS AN AXIS ACROSS THE BAY OF CAMPECHE N TO OVER THE SE CONUS AND THE LOWER MISSISSIPPI VALLEY COVERING THE ENTIRE GULF. THIS FLOW ALOFT IS DRAWING TROPICAL MOISTURE ACROSS MEXICO AND THE W GULF WITH MODERATE SUBSIDENCE AND DRY STABLE AIR COVERING THE FAR SE GULF WATERS S OF A LINE FROM FORT MYERS FLORIDA TO VERACRUZ MEXICO. THE SURFACE RIDGE IS SHIFTING E TO OVER THE W ATLC AS LOWER PRESSURE OVER THE CENTRAL PLAIN STATES IS BEGINNING TO MOVE INTO THE GULF REGION. HOWEVER...THE SOUTHERLY SURFACE FLOW AHEAD OF THIS LOWER PRESSURE CONTINUES TO BANK LOW LEVEL CLOUDS WITH ISOLATED SHOWERS OVER THE NW GULF MAINLY N OF 23N W OF 90W LEAVING THE REMAINDER OF THE GULF WITH MOSTLY CLEAR SKIES AGAIN TONIGHT. A WEAK COLD FRONT IS EXPECTED TO DROP S TO ALONG THE N COASTAL PLAINS AND DISSIPATE THROUGH MON. A SECOND COLD FRONT IS FORECAST TO MOVE OFF THE TEXAS COAST LATE TUE NIGHT. CARIBBEAN SEA... BROAD UPPER RIDGE ANCHORED OVER THE TROPICS COVERS THE CARIBBEAN GIVING THE AREA SW TO W FLOW ALOFT. STRONG SUBSIDENCE AND DRY STABLE AIR COVERS MOST OF THE CARIBBEAN NW OF LINE FROM GUADELOUPE IN THE LEEWARD ISLANDS ALONG 15N73W THEN S TO CENTRAL PANAMA WHILE THE SW FLOW ALOFT IS DRAWING TROPICAL MOISTURE OVER THE SE CARIBBEAN. REMNANT LOW LEVEL MOISTURE REMAINS ACROSS THE NW CARIBBEAN DEVELOPING SCATTERED SHOWERS AND POSSIBLE ISOLATED THUNDERSTORMS N OF 16N W OF 80W INTO THE YUCATAN CHANNEL AND ISOLATED SHOWERS ARE S OF 15N BETWEEN 70W-82W. ATLANTIC OCEAN... NEAR ZONAL WESTERLY FLOW ALOFT DOMINATES THE ATLC N OF 20N WITH MODERATE/STRONG SUBSIDENCE AND DRY STABLE AIR S OF 26N. THE BROAD UPPER RIDGE OVER THE CARIBBEAN ANCHORED IN THE TROPICS DOMINATES THE TROPICAL ATLC. A BROAD SURFACE RIDGE DOMINATES THE ATLC AND ANCHORED BY A 1025 MB HIGH IN THE E ATLC NEAR 29N29W WITH A RIDGE AXIS EXTENDING W TO S FLORIDA. A WEAK SURFACE TROUGH REMAINS EMBEDDED WITHIN THIS SURFACE RIDGE EXTENDING FROM 27N37W TO 24N39W WITH POSSIBLE ISOLATED SHOWERS WITHIN 30 NM EITHER SIDE OF THE SURFACE TROUGH. THE REMAINDER OF THE ATLC IS EXPERIENCING MOSTLY FAIR WEATHER AGAIN TONIGHT. SURFACE RIDGE ACROSS BAHAMAS WILL SHIFT E TODAY IN ADVANCE OF COLD FRONT THAT WILL PUSH S INTO FAR W ATLC MON REACHING FROM BERMUDA TO DAYTONA BEACH MON NIGHT THEN STALL FROM NEAR 32N55W TO S FLORIDA LATE TUE. FOR ADDITIONAL INFORMATION PLEASE VISIT HTTP://WWW.HURRICANES.GOV/MARINE $$ PAW