000 AXNT20 KNHC 301152 TWDAT TROPICAL WEATHER DISCUSSION NWS NATIONAL HURRICANE CENTER MIAMI FL 805 AM EDT SUN SEP 30 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 XXXX UTC. ...SPECIAL FEATURES... HURRICANE NADINE IS LOCATED NEAR 36.6N 37.8W AT 30/0900 UTC OR ABOUT 521 NM WSW OF THE AZORES MOVING NNW NEAR 10 KT. ESTIMATED MINIMUM CENTRAL PRESSURE IS 979 MB. MAXIMUM SUSTAINED WIND SPEED IS 80 KT WITH GUSTS TO 100 KT. PLEASE SEE LATEST NHC FORECAST/ ADVISORY UNDER AWIPS/WMO HEADERS MIATCMAT4/WTNT24 KNHC FOR MORE DETAILS. SCATTERED MODERATE/ISOLATED STRONG CONVECTION FROM 35N-39N BETWEEN 36W-41W. ...TROPICAL WAVES... TROPICAL WAVE CONTINUES EXTENDS FROM 15N21W TO A 1012 MB LOW NEAR 9N25W EMBEDDED WITHIN A MONSOONAL GYRE AND DEEP MOISTURE NOTED ON TOTAL PRECIPITABLE WATER IMAGERY. WIDELY SCATTERED MODERATE CONVECTION IS FROM FROM 7N-15N BETWEEN 20W-32W. TROPICAL WAVE MOVES ACROSS THE CENTRAL TROPICAL ATLC EXTENDING FROM 19N37W TO 10N40W MOVING W AT ABOUT 10 KT. WAVE IS ALONG THE LEADING EDGE OF A BROAD AREA OF DEEP MOISTURE AS DEPICTED BY THE TOTAL PRECIPITABLE WATER IMAGERY. SCATTERED MODERATE CONVECTION IS FROM FROM 13N-20N BETWEEN 35W-41W. TROPICAL WAVE IS NEARLY STATIONARY OVER THE NW CARIBBEAN EXTENDING FROM 24N79W TO 17N83W. AN UPPER LEVEL LOW SPINS OVER THE WAVE DISPLACING THE CONVECTION TO THE E OF THE WAVE AXIS N OF 16N BETWEEN 78W-81W...INCLUDING PORTIONS OF CUBA. THE UPPER LOW SEEMS TO BE TAKING A MORE SIGNIFICANT ROLE IN CONTROLLING THE TILT AND PATH OF THE WAVE. GLOBAL MODELS SUGGEST THIS WAVE WILL BECOME ABSORBED BY THE UPPER LOW/TROUGH DURING THE NEXT 24-36 HOURS. ...ITCZ/MONSOON TROUGH... THE MONSOON TROUGH EXTENDS ACROSS WEST AFRICA TO THE COASTAL WATERS OF MAURITANIA NEAR 17N17W...THEN IT REDEVELOPS FROM A BROAD GYRE CENTERED FROM A 1012 MB LOW AND ASSOCIATED TROPICAL WAVE NEAR 9N25W ALONG 8N33W TO 9N44W...WHERE THE ITCZ BEGINS AND CONTINUES ALONG 7N50W TO THE COAST OF GUYANA NEAR 8N58W. A SURFACE TROUGH IS ANALYZED FROM 15N54W TO 10N56W...JUST N OF THE WESTERN EXTENT OF THE ITCZ AXIS. THIS TROUGH IS ENHANCED BY AN UPPER LEVEL TROUGH NOTED ALONG 49W OVER THE TROPICAL ATLC. SCATTERED MODERATE CONVECTION IS FROM 7N-15N BETWEEN 20W-32W. SIMILAR CONVECTION IS ELSEWHERE WITHIN 70-140 NM ON EITHER SIDE OF THE ITCZ AND MONSOON TROUGH. ...DISCUSSION... GULF OF MEXICO... MOSAIC DOPPLER RADAR IMAGERY CONTINUES TO SHOW CLUSTERS OF SCATTERED MODERATE TO HEAVY SHOWERS AND THUNDERSTORMS ACROSS THE NW AND N-CENTRAL WATERS W OF A LINE FROM THE FLORIDA BIG BEND TO THE COAST OF TAMPICO MEXICO. THE ACTIVITY IS ASSOCIATED TO A VIGOROUS UPPER LEVEL SHORTWAVE/TROUGH MOVING EASTWARD ACROSS SRN TEXAS WITH STRONG DIFFLUENCE AHEAD OF IT...SUPPORTING A LOW PRESSURE SYSTEM CENTERED OVER ERN TEXAS AND ASSOCIATED FRONT EXTENDING SSW ALONG GALVESTON TO TAMPICO. EXPECT THE COLD FRONT TO EXPAND ACROSS THE NW WATERS TODAY WITH GUSTY NW WINDS UP TO 25 KT BEHIND IT. RETURN FLOW AHEAD OF IT MAY INCREASE TO 25 KT AS WELL. THE FRONT IS EXPECTED TO EXTEND FROM SE LOUISIANA TO VERACRUZ MEXICO LATE SUN AND FROM FLORIDA PANHANDLE TO YUCATAN LATE MON...BECOMING STATIONARY FROM TAMPA BAY TO YUCATAN PENINSULA TUE THEN DISSIPATE WED. OTHERWISE...A BROAD/STRONG UPPER RIDGE IS CENTERED OVER ERN MEXICO SPREADING MIDDLE TO UPPER MOISTURE AND CIRRUS FROM THE CONVECTION MENTIONED ABOVE ACROSS THE NRN HALF OF THE GULF BASIN. CARIBBEAN SEA... A NEARLY STNRY UPPER LOW SPINS OVER THE WRN CARIBBEAN CENTERED NEAR 18N84W. THIS FEATURE SITS ON TOP OF A TROPICAL WAVE WHICH SEEMS TO BE AFFECTING ITS WESTWARD TRACK. MODERATE DIFFLUENCE ALOFT E OF THE UPPER LOW COMBINED WITH LOW LEVEL MOISTURE CONVERGENCE RELATED TO THE TROPICAL WAVE IS GENERATING SCATTERED SHOWERS AND ISOLATED THUNDERSTORMS ARE N OF 15N BETWEEN 72W-81W...INCLUDING THE WINDWARD PASSAGE AND INLAND PORTIONS OF HAITI AND ERN CUBA. TO THE S OF THIS AREA OF ACTIVE WEATHER... THE ERN PACIFIC MONSOON TROUGH CROSSES CENTRAL AMERICA ALONG INLAND PORTIONS OF COSTA RICA AND PANAMA TO NRN COLOMBIA GENERATING SIMILAR CONVECTION S OF 12N W OF 72W. THE REMAINDER OF THE CARIBBEAN SEA E OF 72W IS UNDER FAIR SKIES WITH 10-20 KT TRADE WINDS THIS MORNING. HIGH PRESSURE OVER THE CENTRAL ATLC WILL BUILD SW ACROSS THE CARIBBEAN...INCREASING TRADE WIND FLOW THROUGH WEDNESDAY. ATLANTIC OCEAN... BROAD UPPER LEVEL DIFFLUENCE COVERS A GREAT PORTION OF THE WESTERN NORTH ATLC W OF 60W SUPPORTING A COLD FRONT N OF THE DISCUSSION AREA...EXPECTED TO GENERATE GUSTY SOUTHERLY WINDS W OF 75W THROUGH MONDAY NIGHT AND TUESDAY. THEN...THE WEAKENED FRONT WILL ENTER THE FAR NW PORTION OF AREA WEDNESDAY WITH LIGHT WINDS. THE BROAD UPPER DIFFLUENCE LIES BETWEEN AN ELONGATED UPPER LEVEL RIDGE EXTENDING ALONG 32N62W TO 19N71W AND AN UPPER LEVEL TROUGH MOVING OFF THE ERN CONUS SEABOARD. THE OVERALL ACTIVITY SUPPORTS A SURFACE TROUGH ANALYZED FROM 25N69W TO 2171W. DESPITE THE LOCATION OF THE SURFACE FEATURE...NUMEROUS SCATTERED MODERATE CONVECTION COVER AN AREA FROM 21N-28N BETWEEN 63W-70W...AS WELL AS S OF 25N BETWEEN 70W-80W INCLUDING MOST OF THE BAHAMAS. THE REMINDER OF THE ATLC BASIN IS INFLUENCED BY SURFACE RIDGING AROUND A 1028 MB HIGH LOCATED A FEW MILES N OF THE AZORES. FOR ADDITIONAL INFORMATION PLEASE VISIT HTTP://WWW.HURRICANES.GOV/MARINE $$ GARCIA