000 AXNT20 KNHC 140556 TWDAT TROPICAL WEATHER DISCUSSION NWS TPC/NATIONAL HURRICANE CENTER MIAMI FL 205 AM EDT SUN SEP 14 2008 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...METEOROLOGICAL ANALYSIS...WEATHER OBSERVATIONS...AND RADAR. BASED ON 0000 UTC SURFACE ANALYSIS AND SATELLITE IMAGERY THROUGH 0345 UTC. ...SPECIAL FEATURES... TROPICAL STORM IKE WAS DOWNGRADED AT 14/0600 UTC TO TROPICAL DEPRESSION. TROPICAL DEPRESSION IKE IS CENTERED NEAR 35.4N 93.9W AT 14/0600 UTC WHICH IS INLAND OVER ARKANSAS MOVING NNE AT 21 KT. ESTIMATED MINIMUM CENTRAL PRESSURE IS 986 MB. MAXIMUM SUSTAINED WIND SPEED IS 30 KT WITH GUSTS TO 40 KT. PLEASE SEE THE LATEST NHC FORECAST/ADVISORY UNDER AWIPS/WMO HEADERS MIATCMAT4/WTNT24 KNHC AND THE PUBLIC ADVISORY UNDER MIATCPAT4/ WTNT34 KNHC FOR MORE DETAILS. VERY LITTLE OF IKE REMAINS INT HE GULF WATERS TONIGHT. REMNANTS OF OUTFLOW ARE BEING DRAWN S OVER THE W GULF W OF OF A LINE FROM SE LOUISIANA TO MEXICO NEAR VERACRUZ WITH SCATTERED SHOWERS AND POSSIBLE ISOLATED THUNDERSTORMS FROM 24N-26N W OF 94W. ...TROPICAL WAVES... TROPICAL WAVE IS ALONG 24W S OF 13N MOVING W 10-15 KT. THIS WAVE IS LOW AMPLITUDE AND EMBEDDED WITHIN THE ITCZ. ANY SHOWERS AND CONVECTION ARE ASSOCIATED WITH THE ITCZ. TROPICAL WAVE IS ALONG 46W FROM 10N-20N WITH A 1013 MB LOW ANALYZED ALONG THE WAVE AXIS NEAR 16N MOVING W 10-15 KT. WAVE IS EMBEDDED WITHIN A BROAD AREA OF DEEP LAYERED MOISTURE INDICATED BY MIMIC-TPW ANIMATION. SCATTERED MODERATE/ISOLATED STRONG CONVECTION IS FROM 13N-17N BETWEEN 41W AND THE WAVE AXIS. TROPICAL WAVE IS ALONG 65W S OF 20N MOVING W 10-15 KT. ALTHOUGH THIS WAVE IS EMBEDDED WITHIN AN AREA OF DEEP LAYERED MOISTURE WITH A PREDOMINATELY EASTERLY SURFACE FLOW OBSERVED ON SATELLITE IMAGERY. ISOLATED SHOWERS ARE FROM 13N-20N BETWEEN 60W-66W INCLUDING THE LESSER ANTILLES...VIRGIN ISLANDS AND PUERTO RICO. TROPICAL WAVE IS ALONG 76W S OF 19N MOVING W 10-15 KT. ALTHOUGH THIS WAVE IS BENEATH STRONG SOUTHERLY UPPER FLOW WHICH IS ADVECTING UPPER CLOUDS A WEAK INVERTED-V CURVATURE IS OBSERVED ON SATELLITE IMAGERY N OF 16N WITH NO ASSOCIATED SHOWERS OR CONVECTION. ...THE ITCZ... ITCZ AXIS IS ANALYZED ALONG 14N16W 10N21W 6N41W 7N52W 6N59W. CLUSTERS OF SCATTERED MODERATE/ISOLATED STRONG CONVECTION ARE WITHIN 180 NM OF THE ITCZ FROM 22W-46W. ...DISCUSSION... GULF OF MEXICO... REMNANT EFFECTS OF IKE ARE OVER THE W GULF...SEE SPECIAL FEATURES ABOVE. AN UPPER LEVEL HIGH IS CENTERED OVER E TENNESSEE AND AN UPPER LOW IS CENTERED OVER THE YUCATAN CHANNEL NEAR 22N85W. THESE TWO UPPER LEVEL FEATURES ARE PRODUCING GENERALLY STRONG EASTERLY UPPER FLOW OVER THE GULF E OF 90W WITH MOSTLY NORTHERLY UPPER FLOW OVER THE REMAINDER OF THE GULF. MODERATE/ STRONG SUBSIDENCE AND DRY AIR ARE OBSERVED OVER THE AREA N OF 26N E OF 90W AND S OF 26N E OF 93W ACROSS THE FLORIDA PENINSULA GIVING THAT AREA CLEAR SKIES TONIGHT. A WEAK SURFACE RIDGE IS BUILDING FROM THE W ATLC ACROSS THE FLORIDA PENINSULA AND E GULF. S-SE SURFACE WINDS WILL CONTINUE ACROSS MUCH OF THE GULF AHEAD OF A COLD FRONT EXPECTED TO ENTER THE NW GULF LATE SUN. CARIBBEAN SEA... AN UPPER LOW IS CENTERED OVER THE YUCATAN CHANNEL NEAR 22N85W COVERS THE NW CARIBBEAN N OF 15N W OF 78W. AN UPPER HIGH IS CENTERED IN THE S/CENTRAL CARIBBEAN NEAR 12N73W COVERING THE REMAINDER OF THE CARIBBEAN INTO W TROPICAL ATLC. UPPER LEVEL DIFFLUENCE ACROSS THE SW CARIBBEAN IS GENERATING SCATTERED SHOWERS/ISOLATED THUNDERSTORMS S OF 1N W OF 74W TO INLAND OVER PORTIONS OF SOUTH AND CENTRAL AMERICA. SHOWER ACTIVITY OVER THE FAR E CARIBBEAN IS ASSOCIATED WITH THE TROPICAL WAVE...OTHERWISE THE REMAINDER OF THE CARIBBEAN REMAINS TRANQUIL TONIGHT. ATLANTIC OCEAN... INVERTED UPPER TROUGH EXTENDS FROM THE FAR SW ATLC AND THE FLORIDA STRAITS ACROSS THE BAHAMAS TO 28N74W. A SURFACE TROUGH EXTENDS FROM 29N70W TO JUST E OF THE CENTRAL BAHAMAS NEAR 24N74W DRIFTING NW. SCATTERED SHOWERS AND POSSIBLE ISOLATED THUNDERSTORMS ARE WITHIN 75 NM OF LINE FROM 26N67W TO 28N72W. A BENIGN UPPER LOW IS IN THE CENTRAL ATLC NEAR 24N48W WITH A SECOND UPPER LOW IN THE E ATLC NEAR 28N27W. AN UPPER HIGH IS INT HE E TROPICAL ATLC JUST W OF THE CAPE VERDE ISLANDS NEAR 15N27W WITH A SECOND INVERTED UPPER TROUGH IS IN THE W TROPICAL ATLC EXTENDING FROM FRENCH GUIANA TO NEAR 14N50W SEPARATING THE THIS UPPER HIGH FROM THE UPPER HIGH IN THE CARIBBEAN. A BROAD SURFACE RIDGE IS OVER THE ATLC N OF 20N E OF 60W ANCHORED BY A 1021 MB HIGH NEAR 29N47W WITH A NARROW RIDGE EXTENDING W FROM 30N-34N W OF 65W TO THE US E COAST AND A 1018 MB HIGH NEAR 31N72W. $$ WALLACE