000 AXNT20 KNHC 061752 TWDAT TROPICAL WEATHER DISCUSSION NWS TPC/NATIONAL HURRICANE CENTER MIAMI FL 205 PM EDT SAT SEP 06 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 1200 UTC SURFACE ANALYSIS AND SATELLITE IMAGERY THROUGH 1715 UTC. ...SPECIAL FEATURES... TROPICAL STORM HANNA IS CENTERED NEAR 37.6N 76.6W AT 06/1800 UTC OR JUST NORTHEAST OF WILLIAMSBURG VIRGINIA AND ABOUT 48 NM NORTH-NORTHWEST OF NORFOLK VIRGINIA MOVING NE AT 22 KT. ESTIMATED MINIMUM CENTRAL PRESSURE IS 988 MB. MAXIMUM SUSTAINED WIND SPEED IS 45 KT WITH GUSTS TO 55 KT. PLEASE SEE LATEST NHC FORECAST/ADVISORY UNDER AWIPS/WMO HEADERS MIATCMAT3/WTNT23 KNHC FOR MORE DETAILS. HANNA IS NOW INLAND AND IS EXPECTED TO RE-EMERGE INTO THE NW ATLC OFF THE COAST OF NEW ENGLAND DURING THE DAY SUN. HANNA IS EXPECTED TO WEAKEN AND BECOME EXTRATROPICAL WITH AN INCREASE IN FORWARD SPEED OVER THE NEXT 12 TO 24 HOURS. THE HEAVY SHOWERS/THUNDERSTORM ACTIVITY IS INLAND WITH SCATTERED SHOWERS AND POSSIBLE ISOLATED THUNDERSTORMS OFF SHORE FROM NORTH CAROLINA NORTHWARD. HURRICANE IKE IS CENTERED NEAR 21.6N 69.1W AT 06/1800 UTC OR ABOUT 118 NM EAST OF GRAND TURK ISLAND MOVING WSW AT 13 KT. ESTIMATED MINIMUM CENTRAL PRESSURE IS 960 MB. MAXIMUM SUSTAINED WIND SPEED IS 100 KT WITH GUSTS TO 120 KT. PLEASE SEE LATEST NHC FORECAST/ADVISORY UNDER AWIPS/WMO HEADERS MIATCMAT4/WTNT24 KNHC FOR MORE DETAILS. IKE IS AGAIN A CATEGORY THREE HURRICANE ON THE SAFFIR-SIMPSON HURRICANE SCALE. IKE IS NOW FORECAST TO TRACK SOUTH OF THE COOLER WATERS UPWELLED BY HANNA. SCATTERED MODERATE/ISOLATED STRONG CONVECTION IS FROM 20N-23N BETWEEN 66W-71W WITH SCATTERED SHOWERS/ISOLATED THUNDERSTORMS COVERING THE REMAINDER OF THE AREA FROM 18N-24N BETWEEN 65W-72W INCLUDING THE ISLANDS BETWEEN THE VIRGIN ISLANDS AND HISPANIOLA. ...TROPICAL WAVES... TROPICAL WAVE IS W OF THE CAPE VERDE ISLANDS ALONG 29W S OF 18N MOVING W NEAR 15 KT. WEAK CURVATURE IS OBSERVED ON SATELLITE IMAGERY WITH SCATTERED SHOWERS FROM 8N-13N BETWEEN 28W-32W. TROPICAL WAVE IS ALONG 58W/59W S OF 14N MOVING W NEAR 15 KT. WAVE REMAINS LOW AMPLITUDE AND APPEARS EMBEDDED WITHIN THE ITCZ WITH NO ASSOCIATED SHOWERS/CONVECTION. ...THE ITCZ... THE ITCZ AXIS IS ANALYZED ALONG 10N13W 6N25W 13N30W 9N42W 12N55W...BEING DISRUPTED BY THE TWO TROPICAL WAVES. CLUSTERS OF SCATTERED MODERATE/ISOLATED STRONG CONVECTION ARE WITHIN 90/120 NM OF THE ITCZ FROM 50W-62W. CLUSTERS OF SCATTERED MODERATE CONVECTION WITHIN 90/120 NM OF A LINE FROM 9N16W TO 4N28W AND WITHIN 90/120 NM OF THE ITCZ FROM 42W-47W. ...DISCUSSION... GULF OF MEXICO... A BROAD UPPER LONGWAVE TROUGH IS OVER THE US INTO THE NW GULF WITH A STATIONARY FRONT ENTERING THE GULF NEAR THE FLORIDA/ ALABAMA BORDER EXTENDING SW ALONG 27N90W THEN W TO NEAR BROWNSVILLE TEXAS. SCATTERED SHOWERS WITH POSSIBLE ISOLATED THUNDERSTORMS ARE S AND E OF THE FRONT W OF A LINE FROM THE FLORIDA PANHANDLE E OF PANAMA CITY ALONG 26N89W 24N95W TO MEXICO NEAR TUXPAN. A WEAK INVERTED UPPER TROUGH EXTENDS FROM THE COAST OF S MEXICO IN THE BAY OF CAMPECHE NEAR 18N93W TO 22N94W. SCATTERED SHOWERS/THUNDERSTORMS ARE S OF 22N W OF 92W TO INLAND OVER MEXICO. AN UPPER RIDGE IS ANCHORED IN THE W ATLC AND COVERS E GULF E OF 86W. CARIBBEAN SEA... HURRICANE IKE IS GENERATING SHOWERS/THUNDERSTORMS OVER A PORTION OF THE GREATER ANTILLES BETWEEN THE VIRGIN ISLANDS AND HISPANIOLA...SEE SPECIAL FEATURES ABOVE. BROAD UPPER LEVEL RIDGE DOMINATES THE CARIBBEAN ANCHORED IN THE W ATLC GIVING MOST OF THE AREA EASTERLY UPPER WINDS. UPPER DIFFLUENCE IS GENERATING SCATTERED SHOWERS/THUNDERSTORMS S OF 14N W OF 81W TO THE COAST OF PANAMA TO NICARAGUA AND IS GENERATING ISOLATED SHOWERS ACROSS THE NW CARIBBEAN NW OF A LINE FROM CUBA NEAR 22N80W TO BELIZE NEAR 17N88W. THE ITCZ EXTENDS INTO THE SE CARIBBEAN ACROSS THE WINDWARD ISLANDS TO JUST OF THE ABC ISLANDS GENERATING SCATTERED SHOWERS/ISOLATED THUNDERSTORMS S OF 15N E OF 65W TO OVER THE WINDWARD ISLANDS. STRONG SUBSIDENCE/DRY AIR IS ACROSS THE CENTRAL CARIBBEAN BETWEEN 65W-80W. ATLANTIC OCEAN... HURRICANE IKE IS THE MAIN CONCERN FOR THE NEXT FEW DAYS OVER THE SW ATLC...SEE SPECIAL FEATURES ABOVE. A BROAD UPPER RIDGE COVERS THE W ATLC ANCHORED NEAR 29N76W AND EXTENDING S OVER MUCH OF THE CARIBBEAN. A SHEAR AXIS EXTENDS FROM THE E ATLC NEAR 32N30W THEN SW ACROSS THE CENTRAL ATLC TO AN UPPER LOW NEAR 22N47W IN THE TROPICS TO THE LESSER ANTILLES NEAR 16N61W. UPPER DIFFLUENCE IS GENERATING SCATTERED SHOWERS/ISOLATED THUNDERSTORMS FROM 17N-20N BETWEEN 60W-62W...FROM 25N-29N BETWEEN 58W-62W...AND FROM 21N-23N BETWEEN 50W-52W. A REMNANT OF JOSEPHINE...A 1008 MB LOW IS CENTERED NEAR 16N37W WITH THE LAST ADVISORY WRITTEN AT 06/0900 UTC. SCATTERED MODERATE/ISOLATED STRONG CONVECTION IS FROM 18N-21N BETWEEN 37W-39W. AN E/W UPPER RIDGE EXTENDS FROM W AFRICA ALONG 23N TO 40W AND S OF 30N. ALSO AT THE SURFACE IS A BROAD SURFACE RIDGE THAT COVERS THE AREA N OF 20N E OF 50W AND N OF 27N E OF 72W ANCHORED N OF THE REGION AND A WEAK 1020 MB IN THE E ATLC NEAR 29N25W. $$ WALLACE