000 AXNT20 KNHC 071148 TWDAT TROPICAL WEATHER DISCUSSION NWS TPC/NATIONAL HURRICANE CENTER MIAMI FL 805 AM EDT SUN SEP 07 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 0600 UTC SURFACE ANALYSIS AND SATELLITE IMAGERY THROUGH 1115 UTC. ...SPECIAL FEATURES... HANNA LOSES TROPICAL CHARACTERISTICS AS IT MOVES THROUGH NEW ENGLAND. AT 07/0900 UTC...ITS CENTER IS NEAR 42.6N 70.0W OR OR ABOUT 50 NM...100 KM...NORTH OF CHATHAM MASSACHUSETTS AND ABOUT 305 NM...560 KM...WEST-SOUTHWEST OF HALIFAX NOVA SCOTIA MOVING NE AT 31 KT. THIS MOTION IS EXPECTED TO CONTINUE FOR THE NEXT 24 HOURS. ESTIMATED MINIMUM CENTRAL PRESSURE IS 995 MB. MAXIMUM SUSTAINED WIND SPEED IS 40 KT WITH GUSTS TO 55 KT. PLEASE SEE LATEST NHC FORECAST/ ADVISORY UNDER AWIPS/WMO HEADERS MIATCMAT3/WTNT23 KNHC FOR MORE DETAILS. HANNA IS EXPECTED TO PRODUCE ADDITIONAL RAINFALL ACCUMULATIONS OF 1 TO 2 INCHES ACROSS CENTRAL TO SOUTHERN MAINE EARLY SUNDAY MORNING...WITH THE RAINFALL ENDING ACROSS MAINE BY AROUND SUNRISE. THE LAST ADVISORY WAS ISSUED BY THE NATIONAL HURRICANE CENTER ON THIS SYSTEM AT 07/0900 UTC. HURRICANE IKE IS CENTERED NEAR 21.0N 72.8W AT 07/1200 UTC OR JUST EAST OF GREAT INAGUA ISLAND MOVING JUST SOUTH OF DUE WEST AT 12 KT. A WEST TO WEST-SOUTHWEST MOTION IS EXPECTED TO CONTINUE TODAY WITH A TURN TOWARD THE W-NW EXPECTED ON MONDAY. ON THIS TRACK...THE CORE OF THE HURRICANE WILL MOVE THROUGH THE SOUTHEASTERN BAHAMAS THIS MORNING AND MOVE NEAR OR OVER EASTERN CUBA TONIGHT...AND NEAR OR OVER CENTRAL CUBA LATE MONDAY. ESTIMATED MINIMUM CENTRAL PRESSURE IS 949 MB. MAXIMUM SUSTAINED WIND SPEED IS 115 KT WITH GUSTS TO 140 KT. PLEASE SEE LATEST NHC FORECAST/ADVISORY UNDER AWIPS/WMO HEADERS MIATCMAT4/ WTNT24 KNHC FOR MORE DETAILS. IKE IS AN EXTREMELY DANGEROUS CATEGORY FOUR HURRICANE ON THE SAFFIR-SIMPSON SCALE HEADING FOR GREAT INAGUA ISLAND IN THE SOUTHEASTERN BAHAMAS. RAINFALL AMOUNTS OF 4 TO 8 INCHES WITH ISOLATED MAXIMUM AMOUNTS OF 12 INCHES ARE EXPECTED OVER THE TURKS AND CAICOS ISLANDS AND THE SOUTHEASTERN BAHAMAS. HISPANIOLA AND EASTERN CUBA COULD SEE 6 TO 12 INCHES OF RAIN WITH ISOLATED MAXIMUM AMOUNTS OF UP TO 20 INCHES POSSIBLE. THESE RAINS WILL LIKELY CAUSE LIFE-THREATENING FLASH FLOODS AND MUDSLIDES OVER MOUNTAINOUS TERRAIN. ...TROPICAL WAVES... A TROPICAL WAVE IS ALONG 33W/34W S OF 15N MOVING W 10-15 KT. ISOLATED MODERATE CONVECTION IS NEAR THE SOUTHERN END OF THE WAVE AXIS FROM 6N-8N. SCATTERED SHOWERS ARE AHEAD OF THE WAVE LINE NEAR 11N36W. A TROPICAL WAVE IS ALONG 59W SOUTH 17N MOVING W 10-15 KT. THE WAVE IS CROSSING THE ISLAND OF BARBADOS...WHICH IS REPORTING HEAVY TSTMS AND SUSTAINED WINDS OF 25 KT FROM THE SE. A CLUSTER OF MODERATE TO ISOLATED STRONG CONVECTION IS OVER THAT ISLAND. SFC DATA AND AN EARLIER ASCAT PASS...BOTH SHOWED VERY WELL THE WIND SHIFT ASSOCIATED WITH THE WAVE. THE WAVE SHOWS UP ON THE THE TPW PRODUCT FROM CIMSS WHERE A BULGE OF MOISTURE MAXIMUM IS NOTED. 850 MB SATELLITE DERIVED VORTICITY ALSO SUPPORTS THE POSITION OF THE WAVE AXIS. ...THE ITCZ... THE ITCZ AXIS IS ALONG 13N17W 8N23W 8N31W 10N40W 11N58W. BESIDES THE CONVECTION MENTIONED IN THE TROPICAL WAVE SECTION... A CLUSTER OF MODERATE/ISOLATED STRONG CONVECTION IS FROM 5N-7N BETWEEN 27W-29W. SCATTERED MODERATE CONVECTION IS NEAR 11N22W AND 5N31W. ...DISCUSSION... GULF OF MEXICO... AS OF 0900 UTC...A WEAKENING STATIONARY FRONT EXTENDS FROM THE W FLORIDA PANHANDLE TO THE DEEP SOUTH TEXAS. THE FRONT IS SLIGHTLY MOVING N PARTICULARLY ON THE WESTERN PART. SCATTRED SHOWERS AND ISOLATED TSTMS ARE ALONG THE FRONTAL BOUNDARY. A SURFACE TROUGH REMAINS OVER THE BAY OF CAMPECHE ALONG 93W/94W S OF 23N. CONVECTION ASSOCIATED WITH THIS TROUGH HAS INCREASED OVERNIGHT AND NOW SATELLITE IMAGERY SHOWS A LARGE AREA OF MODERATE TO STRONG CONVECTION OVER THE BAY OF CAMPECHE AND SE MEXICO NEAR VERACRUZ WHICH IS REPORTING LIGHT TO MODERATE. NE WINDS OF 15-20 KT ARE NOTED WHILE WINDS HAS VEERED TO THE E BEHIND THE FRONTAL SYSTEM. A SFC RIDGE FROM THE ATLC DOMINATES THE EASTERN PORTION OF THE GULF AND THE STATE OF FLORIDA WITH A 1016 MB HIGH LOCATED NEAR 28N85W. IN THE UPPER LEVELS...A MID/UPPER LEVEL RIDGE COVERS MOST OF THE AREA WITH A LONGWAVE TROUGH OVER THE CENTRAL U.S. CLIPPING THE FAR N CENTRAL GULF. THIS UPPER-LEVEL TROUGH IS SUPPORTING THE AFOREMENTIONED FRONTAL BOUNDARY. LOOKING AHEAD...MAJOR HURRICANE IKE CURRENTLY EAST OF GREAT INAGUA ISLANDS IN THE SE BAHAMAS IS FORECAST TO ENTER THE SE GULF TUE THEN TRACKS NW TO N CENTRAL GULF THU. ONCE IKE MOVES INTO THE SE GULF...CONDITIONS APPEAR FAVORABLE FOR STRENGTHENING. CARIBBEAN SEA... ALL THE ATTENTION REMAINS FOCUSED ON THE EXTREMELY DANGEROUS HURRICANE IKE THAT IS FORECAST TO MOVE OVER OR NEAR EASTERN CUBA TONIGHT AND EARLY MONDAY. OUTER RAINBANDS ASSOCIATED WITH IKE ARE AFFECTING WESTERN PUERTO RICO AND HISPANIOLA. THE SAN JUAN DOPPLER RADAR DEPICTS A BAND OF SHOWERS WITH EMBEDDED TSTMS OVER THE MONA PASSAGE AND THE SW PORTION OF PUERTO RICO UNDER A SE WIND FLOW. THE FIRST RAINBAND ASSOCIATED WITH IKE IS REACHING THE EASTERNMOST TIP OF CUBA. SEE SPECIAL FEATURES FOR DETAILS ABOUT IKE. THE REMAINDER OF THE BASIN IS PRETTY QUIET EARLY THIS MORNING WITH LOW TOPPED SHOWERS AND HIGH CLOUDS FROM THE OUTFLOW OF IKE. ALOFT...UPPER-LEVEL ELY FLOW DOMINATES THE CENTRAL AND WESTERN CARIBBEAN WHILE AN UPPER-LEVEL TROUGH FROM THE CENTRAL ATLC ENTERS THE E CARIBBEAN BETWEEN GUADALOUPE AND MARTINIQUE. ATLANTIC OCEAN... MAJOR HURRICANE IKE IS THE MAIN CONCERN FOR THE NEXT FEW DAYS OVER THE SW ATLC INCLUDING THE BAHAMAS...SEE SPECIAL FEATURES ABOVE. IN THE TROPICS...A 1010 MB SFC LOW...REMNANTS OF JOSEPHINE...IS CENTERED NEAR 17N39W. A SWIRL OF MAINLY LOW CLOUDS DEFINES THE LOW CENTER WHILE CONVECTION HAS SIGNIFICANTLY INCREASED IN THE NW QUADRANT OVER THE PAST FEW HOURS. A LARGE CLUSTER OF MODERATE TO STRONG CONVECTION COVERS THE AREA FROM FROM 17N-21N BETWEEN 40W-43W. UPPER-LEVEL WINDS ARE CURRENTLY UNFAVORABLE FOR RE-DEVELOPMENT TO OCCUR. A 1026 MB HIGH LOCATED NEAR 37N54W EXTENDS A RIDGE SWWD INTO THE E PORTION OF THE GULF OF MEXICO...AND ALSO ENVELOPS THE N PORTION OF THE FORECAST AREA. A MID-UPPER LEVEL RIDGE OVER THE CENTRAL AND W ATLC INTO THE FLORIDA PENINSULA AND THE EASTERN GULF IS STEERING IKE WWD. AN UPPER-LEVEL LOW OVER THE CENTRAL ATLC NEAR 20N54W HAS A TROUGH EXTENDING SW INTO THE E CARIBBEAN TO ANOTHER UPPER-LEVEL LOW LOCATED NEAR 13N66W. THE E ATLC IS UNDER THE INFLUENCE OF RIDGE ANCHORED ON A HIGH SITUATED NEAR 20N32W. A JET-STREAM BRANCH IS PRODUCING ABUNDANT CLOUDINESS WITH POSSIBLE SHOWERS OVER THE CANARY ISLANDS. $$ GR