000 AXNT20 KNHC 091155 TWDAT TROPICAL WEATHER DISCUSSION NWS NATIONAL HURRICANE CENTER MIAMI FL 805 AM EDT SUN OCT 09 2011 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 1045 UTC. ...SPECIAL FEATURES... AN AREA OF BROAD SURFACE TROUGHING OVER THE W ATLC AND E GULF OF MEXICO IS BEING INDUCED BY AN UPPER LEVEL TROUGH THAT EXTENDS FROM W TENNESSEE INTO THE GULF OF MEXICO TO AN UPPER LOW NEAR 25N83W SUPPORTING A SURFACE TROUGH THAT AT 09/0900 UTC EXTENDS FROM THE N COAST OF CUBA NEAR 22N79W BETWEEN THE BAHAMAS AND FLORIDA TO 31N79W. A LARGE AREA OF SCATTERED SHOWERS/ISOLATED THUNDERSTORMS ARE OVER THE W ATLC S OF 30N TO OVER THE GREATER ANTILLES FROM THE MONA PASSAGE TO E CUBA BETWEEN 68W-77W AND N OF 24N TO BEYOND 32N BETWEEN 77W-85W. SURFACE PRESSURES ARE SLOWLY FALLING. LITTLE CHANGE IN THE ORGANIZATION OF THIS DISTURBANCE HAS TAKEN PLACE DURING THE LAST SEVERAL HOURS. SOME DEVELOPMENT INTO A TROPICAL OR SUBTROPICAL CYCLONE IS POSSIBLE DURING THE NEXT FEW DAYS AS IT MOVES NORTHWESTWARD 5 TO 10 MPH. REGARDLESS OF DEVELOPMENT...STRONG GUSTY WINDS AND LOCALLY HEAVY RAINFALL ARE EXPECTED OVER THE NORTHERN BAHAMAS AND PORTIONS OF THE FLORIDA PENINSULA TODAY. THESE CONDITIONS ARE EXPECTED TO SPREAD NORTHWARD INTO EASTERN PORTIONS OF GEORGIA AND SOUTH CAROLINA DURING THE NEXT DAY OR TWO. FOR ADDITIONAL INFORMATION SPECIFIC TO YOUR AREA...PLEASE SEE STATEMENTS ISSUED BY YOUR LOCAL WEATHER OFFICE. ...TROPICAL WAVES... TROPICAL WAVE IS ANALYZED FROM 17N52W ALONG 11N53W TO 6N53W MOVING W 10-15 KT. WAVE IS EMBEDDED WITHIN A SPIKE OF DEEP LAYER MOISTURE AS DEPICTED ON THE TOTAL PRECIPITABLE WATER IMAGERY. WAVE IS CO-LOCATED WITH AN UPPER LEVEL TROUGH WITH SCATTERED SHOWERS WITHIN 90 NM EITHER SIDE OF THE WAVE AXIS N OF 11N. ...THE ITCZ/THE MONSOON TROUGH... THE MONSOON TROUGH EXTENDS INTO THE E TROPICAL ATLC NEAR 17N16W ALONG 17N19W THEN S ALONG 10N22W TO 8N25W. THE ITCZ EXTENDS FROM 7N27W ALONG 6N35W 9N42W TO 9N51W. CLUSTERS OF SCATTERED MODERATE/STRONG CONVECTION ARE OFF THE COAST OF W AFRICA FROM 4N-9N BETWEEN 9W-19W. CLUSTERS OF SCATTERED MODERATE/ISOLATED STRONG CONVECTION ARE FROM 2N-10N BETWEEN 28W-39W AND FROM 5N-12N BETWEEN 41W-52W. ...DISCUSSION... GULF OF MEXICO... A SHARP UPPER TROUGH ASSOCIATED WITH THE AREA DESCRIBED IN THE SPECIAL FEATURES SECTION COVERS THE E GULF E OF 90W. A BROAD UPPER RIDGE EXTENDS FROM THE E PACIFIC REGION ACROSS S MEXICO AND THE W GULF FROM NEAR VERACRUZ TO THE LOUISIANA/TEXAS BORDER ENHANCING THE ACTIVITY INLAND OVER TEXAS AND WITHIN 60 NM ALONG THE COAST OF TEXAS BETWEEN GALVESTON AND MATAGORDA BAY. A BROAD SURFACE RIDGE COVERS THE GULF ANCHORED OVER THE MID ATLC STATES WITH A RIDGE AXIS EXTENDING ACROSS N GEORGIA TO S ALABAMA INTO THE GULF TO NEAR 25N94W. TIGHT PRESSURE GRADIENT BETWEEN THIS SURFACE RIDGE AND A SURFACE TROUGH IN THE W ATLC IS PRODUCING STRONG EASTERLY SURFACE FLOW TO GALE FORCE OVER THE GULF AND WILL PERSIST THROUGH TONIGHT. THIS SURFACE FLOW IS GENERATING SCATTERED SHOWERS AND POSSIBLE ISOLATED THUNDERSTORMS OVER THE N GULF N OF 25N W OF 85W. A SURFACE LOW IS EXPECTED TO DEVELOP OVER THE E GULF LATER TODAY. THE LOW WILL DRIFT NW ACROSS NE GULF THROUGH MON SUBSIDING WINDS AS IT MOVES INLAND OVER NW FLORIDA. A WEAK TROUGH WILL EXTEND FROM LOW SW TO YUCATAN TUE AND WED THEN SHIFT E ACROSS FLORIDA AND SE GULF THU. CARIBBEAN SEA... THE UPPER TROUGH OVER THE GULF OF MEXICO EXTENDS OVER THE W CARIBBEAN THROUGH THE YUCATAN CHANNEL TO OVER HONDURAS AND NICARAGUA DRAWING TROPICAL MOISTURE N OVER THE CENTRAL CARIBBEAN GENERATING SCATTERED SHOWERS/ISOLATED THUNDERSTORMS N OF 15N TO OVER CUBA BETWEEN 76W-80W. AN UPPER RIDGE EXTENDS OVER THE E CARIBBEAN EXTENDING FROM THE COAST OF VENEZUELA NEAR 11N69W THROUGH THE MONA PASSAGE ENHANCING SCATTERED SHOWERS/ THUNDERSTORMS OVER THE CENTRAL CARIBBEAN BETWEEN 68W-76W. THE MONSOON TROUGH EXTENDS FROM COLOMBIA NEAR 12N71W ALONG 12N76W ACROSS S NICARAGUA INTO THE E PACIFIC REGION NEAR 11N84W GENERATING SCATTERED SHOWERS/ISOLATED THUNDERSTORMS S OF 13N BETWEEN 75W-80W AND S OF 10N BETWEEN 80W-84W. THIS IS LEAVING THE FAR E AND FAR W CARIBBEAN UNDER MOSTLY CLEAR SKIES THIS MORNING. THE WEAK PRESSURE PATTERN WILL PERSIST THROUGH THU. ATLANTIC OCEAN... THE UPPER TROUGH OVER THE E GULF OF MEXICO EXTENDS OVER THE FAR W ATLC W OF 77W AND IS ASSOCIATED WITH THE AREA IN THE SPECIAL FEATURES SECTION ABOVE. A BROAD UPPER RIDGE COVERS THE REMAINDER OF THE W ATLC BETWEEN 55W-76W ENHANCING THE ACTIVITY IN THE SPECIAL FEATURES. A BROAD SURFACE RIDGE COVERS THE W AND CENTRAL ATLC N OF 24N W OF 50W TO OVER THE E CONUS AND GULF OF MEXICO ANCHORED OVER THE MID ATLC STATES. TIGHT PRESSURE GRADIENT BETWEEN THIS SURFACE RIDGE AND THE SURFACE TROUGH OVER THE W ATLC IS GIVING THE FAR W ATLC STRONG EASTERLY WINDS TO GALE FORCE. AN UPPER TROUGH COVERS THE NW ATLC INTO THE CENTRAL ATLC N OF 26N BETWEEN 41W-60W SUPPORTING A COLD FRONT THAT ENTERS THE REGION NEAR 32N41W ALONG 27N45W TO 24N52W WHERE IT CONTINUES AS A SURFACE TROUGH ALONG 23N61W TO 23N67W. SCATTERED SHOWERS AND POSSIBLE ISOLATED THUNDERSTORMS ARE WITHIN 60/90 NM E OF THE FRONT AND WITHIN 45 NM EITHER SIDE OF THE SURFACE TROUGH. A SURFACE RIDGE COVERS THE E ATLC WITH THE AXIS EXTENDING THROUGH 32N30W ALONG 26N36W TO A 1017 MB HIGH NEAR 22N45W. STRONG SURFACE RIDGE OVER THE W ATLC WILL MAINTAIN STRONG NE WINDS THROUGH MON. FOR ADDITIONAL INFORMATION PLEASE VISIT HTTP://WWW.HURRICANES.GOV/MARINE $$ PAW