000 AXNT20 KNHC 300603 TWDAT TROPICAL WEATHER DISCUSSION NWS NATIONAL HURRICANE CENTER MIAMI FL 205 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 0000 UTC SURFACE ANALYSIS AND SATELLITE IMAGERY THROUGH 0545 UTC. ...SPECIAL FEATURES... HURRICANE NADINE IS LOCATED NEAR 35.6N 37.5W AT 30/0300 UTC OR ABOUT 525 NM WSW OF THE AZORES MOVING NNW NEAR 9 KT. ESTIMATED MINIMUM CENTRAL PRESSURE IS 984 MB. MAXIMUM SUSTAINED WIND SPEED IS 75 KT WITH GUSTS TO 90 KT. PLEASE SEE LATEST NHC FORECAST/ ADVISORY UNDER AWIPS/WMO HEADERS MIATCMAT4/WTNT24 KNHC FOR MORE DETAILS. SCATTERED MODERATE/ISOLATED STRONG CONVECTION FROM 34N-39N BETWEEN 35W-41W. ...TROPICAL WAVES... TROPICAL WAVE CONTINUES E OF CAPE VERDE ISLANDS EXTENDING FROM 17N20W TO 11N23W EMBEDDED WITHIN A MONSOONAL GYRE WITH DEEP MOISTURE NOTED ON ON TOTAL PRECIPITABLE WATER IMAGERY. WAVE IS FORECAST TO ROTATE TO A MORE N/S ORIENTATION OVER THE NEXT 24 HOURS THEN WILL MOVE MORE WESTWARD. WIDELY SCATTERED MODERATE CONVECTION IS FROM 10N-17N BETWEEN 20W-27W. TROPICAL WAVE MOVES ACROSS THE CENTRAL TROPICAL ATLC EXTENDING FROM 17N33W TO 10N39W 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 14N-18N BETWEEN 35W-38W. TROPICAL WAVE IS NEARLY STATIONARY OVER THE NW CARIBBEAN EXTENDING ALONG 83W S OF 21N. AN UPPER LEVEL LOW SPINS OVER THE WAVE DISPLACING THE CONVECTION WELL TO THE E OF THE WAVE AXIS N OF 15N BETWEEN 72W-81W...INCLUDING THE WINDWARD PASSAGE AND INLAND PORTIONS OF HAITI AND ERN 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 FROM THE AFRICAN COAST OF SENEGAL NEAR 14N17W ALONG 8N27W 10N33W TO 7N44W...WHERE THE ITCZ BEGINS CONTINUING TO THE COAST OF GUYANA NEAR 7N58W. A SURFACE TROUGH IS ANALYZED FROM 16N51W TO 11N54W...JUST N OF THE WESTERN EXTENT OF THE ITCZ AXIS. SCATTERED MODERATE CONVECTION IS FROM 10N-12N BETWEEN 52W-55W...ENHANCED BY AN UPPER LEVEL TROUGH NOTED ALONG 49W OVER THE TROPICAL ATLC. 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 MOVING ENE ACROSS THE NW AND N-CENTRAL WATERS N OF 26N W OF 86W...HEADING TO THE FAR NE GULF THIS EVENING. 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 AND ASSOCIATED FRONT SOON TO ENTER THE NW BASIN. EXPECT THE COLD FRONT TO SWEEP ACROSS THE NW AND N-CENTRAL 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 COSTA RICA AND PANAMA TO NRN COLOMBIA GENERATING SIMILAR CONVECTION S OF 12N W OF 72W. THE REMAINDER OF THE CARIBBEAN SEA IS UNDER FAIR SKIES THIS EVENING. 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 MON NIGHT AND TUE. 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 PAIR OF SURFACE TROUGHS ANALYZED FROM 32N71W TO 2976W...AND FROM 25N69W TO 21N68W. DESPITE THE LOCATIONS OF THESE SURFACE FEATURES...NUMEROUS SCATTERED MODERATE CONVECTION COVER AN AREA S OF 24N BETWEEN 70W-80W...AND N OF 22N BETWEEN 63W-70W...WHERE THE SHARPEST UPPER LEVEL CYCLONIC TURNING IS NOTED. THE REMINDER OF THE ATLC BASIN IS INFLUENCED BY SURFACE RIDGING AROUND A 1030 MB HIGH LOCATED OVER THE AZORES. FOR ADDITIONAL INFORMATION PLEASE VISIT HTTP://WWW.HURRICANES.GOV/MARINE $$ GARCIA