000 AXNT20 KNHC 051800 TWDAT TROPICAL WEATHER DISCUSSION NWS TPC/NATIONAL HURRICANE CENTER MIAMI FL 205 PM EDT FRI SEP 05 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 1715 UTC. ...SPECIAL FEATURES... TROPICAL STORM HANNA IS CENTERED NEAR 29.8N 78.5W AT 05/1800 UTC OR ABOUT 140 NM EAST-NORTHEAST OF DAYTONA BEACH FLORIDA AND ABOUT 270 NM SOUTH OF WILMINGTON NORTH CAROLINA MOVING N AT 17 KT. THE LATEST MINIMUM CENTRAL PRESSURE REPORTED BY THE HURRICANE HUNTER IS 981 MB. MAXIMUM SUSTAINED WIND SPEED IS 60 KT WITH GUSTS TO 75 KT. SEE LATEST NHC FORECAST/ADVISORY UNDER AWIPS/WMO HEADERS MIATCMAT3/WTNT23 KNHC FOR MORE DETAILS. SOUTHERLY UPPER WINDS ARE PRODUCING SHEAR OVER HANNA AND COUPLED WITH DRY AIR ARE LIMITING CONVECTION TO THE S OF THE CENTER. HANNA IS NOT FORECAST TO BECOME A HURRICANE PRIOR TO LANDFALL BUT IT WOULD ONLY TAKE A SMALL INCREASE IN WIND SPEED FOR HANNA TO BECOME A HURRICANE. SCATTERED MODERATE/STRONG CONVECTION IS FROM 28N-31N BETWEEN 78W-80W WITH SCATTERED SHOWERS/ THUNDERSTORMS COVERING THE REMAINDER OF THE AREA N OF 26N TO BEYOND 32N W OF 77W TO INLAND OVER THE SE US FROM FLORIDA TO NORTH CAROLINA. HURRICANE IKE IS CENTERED NEAR 23.2N 62.7W AT 05/1500 UTC OR ABOUT 370 NM NORTH OF THE LEEWARD ISLANDS AND ABOUT 480 NM EAST-NORTHEAST OF GRAND TURK ISLAND MOVING W AT 14 KT. ESTIMATED MINIMUM CENTRAL PRESSURE IS 954 MB. MAXIMUM SUSTAINED WIND SPEED IS 105 KT WITH GUSTS TO 130 KT. SEE LATEST NHC FORECAST/ADVISORY UNDER AWIPS/WMO HEADERS MIATCMAT4/WTNT24 KNHC FOR MORE DETAILS. IKE IS A DANGEROUS CATEGORY THREE HURRICANE ON THE SAFFIR- SIMPSON HURRICANE SCALE. NORTHERLY UPPER WINDS HAVE PRODUCED SHEAR OVER IKE THUS WEAKENING IT SLIGHTLY. THIS SHEAR IS EXPECTED TO DECREASE IN ABOUT 24 HOURS AND IKE IS EXPECTED TO STRENGTHEN AGAIN IN FOLLOWING COUPLE DAYS. SCATTERED MODERATE/ STRONG CONVECTION IS FROM 20N-24N BETWEEN 61W-65W WITH SCATTERED SHOWERS AND POSSIBLE ISOLATED THUNDERSTORMS FROM 17N-24N BETWEEN 60W-65W INCLUDING THE LEEWARD AND VIRGIN ISLANDS. TROPICAL STORM JOSEPHINE IS CENTERED NEAR 15.8N 34.8W AT 05/1500 UTC OR ABOUT 600 NM WEST OF THE SOUTHERNMOST CAPE VERDE ISLANDS MOVING WNW AT 7 KT. ESTIMATED MINIMUM CENTRAL PRESSURE IS 1003 MB. MAXIMUM SUSTAINED WIND SPEED IS 40 KT WITH GUSTS TO 50 KT. SEE LATEST NHC FORECAST/ADVISORY UNDER AWIPS/WMO HEADERS MIATCMAT5/WTNT25 KNHC FOR MORE DETAILS. STRONG SOUTHERLY UPPER WINDS HAVE COMPLETELY EXPOSED THE LOW LEVEL CENTER OF JOSEPHINE WITH NO REMAINING DEEP CONVECTION. THIS SHEAR IS EXPECTED OVER THE AREA FOR THE NEXT COUPLE OF DAYS THEN WEAKEN. THEREFORE IF THE LOW CENTER REMAINS INTACT...JOSEPHINE COULD RESTRENGTHEN AT THAT TIME. SCATTERED SHOWERS AND POSSIBLE ISOLATED THUNDERSTORMS ARE FROM 14N-19N BETWEEN 32W-38W. ...TROPICAL WAVES... TROPICAL WAVE IS OVER THE CAPE VERDE ISLANDS ALONG 23W S OF 19N MOVING W 10-15 KT. THIS WAVE IS JUST FAR ENOUGH E OF T.S. JOSEPHINE TO NOT HAVE EFFECT ON THIS WAVE. WEAK INVERTED-V CURVATURE IS OBSERVED ON SATELLITE IMAGERY WITH A SMALL AREA OF SCATTERED MODERATE/ISOLATED STRONG CONVECTION OVER THE NORTHERN MOST CAPE VERDE ISLANDS FROM 16N-18N BETWEEN 23W-26W AND S OF THE CAPE VERDE ISLANDS FROM 11N-12N BETWEEN 24W-26W. TROPICAL WAVE IS ALONG 53W S OF 15N MOVING W NEAR 10-15 KT. WAVE REMAINS LOW AMPLITUDE AND HAS SLOWED OVER THE PAST 24 HOURS. WAVE IS EMBEDDED WITHIN AN ACTIVE PART OF THE ITCZ BUT DOES NOT EXHIBIT THE TYPICAL INVERTED PATTERN. ...THE ITCZ... THE ITCZ AXIS IS ANALYZED ALONG 17N16W 15N28W 12N44W 9N62W... DISRUPTED BY THE TWO TROPICAL WAVE AND T.S. JOSEPHINE. CLUSTERS OF SCATTERED MODERATE/ISOLATED STRONG CONVECTION ARE FROM 8N-13N BETWEEN 43W-49W AND FROM 10N-14N BETWEEN 49W-57W. ...DISCUSSION... GULF OF MEXICO... A BROAD UPPER LONGWAVE TROUGH IS OVER THE US INTO THE NW GULF WITH A STATIONARY FRONT ENTERING THE GULF ALONG THE CENTRAL MISSISSIPPI COAST ACROSS THE MISSISSIPPI DELTA OF LOUISIANA EXTENDING SW TO JUST S OF BROWNSVILLE TEXAS. THE FRONT W OF 94W IS BEGINNING TO WEAKEN. SCATTERED SHOWERS/ISOLATED THUNDERSTORMS ARE WITHIN 120 NM SE OF THE FRONT. A WEAK INVERTED UPPER TROUGH EXTENDS FROM THE COAST OF S MEXICO IN THE CENTRAL BAY OF CAMPECHE NW ALONG THE COAST TO NEAR TAMPICO MEXICO. A SURFACE TROUGH EXTENDS FROM 26N91W TO THE E BAY OF CAMPECHE NEAR 20N92W. UPPER LEVEL DIFFLUENCE IS GENERATING SCATTERED SHOWERS/ THUNDERSTORMS WITHIN 120 NM ALONG THE COAST OF MEXICO FROM VERACRUZ TO JUST N OF TAMPICO. AN MID/UPPER TROUGH IS IN THE SE GULF FROM FLORIDA BAY TO A WEAK UPPER LOW JUST N OF THE YUCATAN CHANNEL. SCATTERED SHOWERS AND POSSIBLE ISOLATED THUNDERSTORMS ARE OVER THE FLORIDA PENINSULA AND COULD DRIFT INTO THE FAR E GULF COMPLIMENTS OF T.S. HANNA. THE FRONT IS EXPECTED TO DISSIPATE BY SAT WITH A WEAK HIGH PRESSURE BUILDING OVER THE N GULF DURING THE FIRST OF THE WORK WEEK AS HANNA MOVES OUT OF THE REGION TONIGHT/SAT MORNING. CARIBBEAN SEA... BROAD UPPER LEVEL RIDGE DOMINATES THE CARIBBEAN ANCHORED IN THE CENTRAL ATLC E OF T.S. HANNA WITH THE UPPER TROUGH OVER THE SE GULF OF MEXICO COVERING THE FAR NW CARIBBEAN. ISOLATED SHOWERS AND POSSIBLE ISOLATED THUNDERSTORMS DOT THE W/CENTRAL CARIBBEAN W OF A LINE FROM SW HAITI ALONG 12N78W TO THE COAST OF COSTA RICA/NICARAGUA AND S OF A LINE FROM CENTRAL CUBA NEAR 21N79W ACROSS THE CAYMAN ISLANDS TO THE YUCATAN PENINSULA JUST N OF BELIZE. STRONG SUBSIDENCE AND DRY AIR ARE PUSHING ACROSS THE CARIBBEAN E OF 74W CLEARING THE REMAINDER OF THE CARIBBEAN WITH THE EXCEPTION OF THE LEEWARD/VIRGIN ISLANDS WHERE THERE IS ACTIVITY ASSOCIATED WITH HURRICANE IKE. ATLANTIC OCEAN... TWO TROPICAL STORMS AND ONE HURRICANE ARE LOCATED IN THE DISCUSSION AREA...SEE SPECIAL FEATURES ABOVE FOR DETAILS. A BROAD UPPER RIDGE COVERS THE W ATLC ANCHORED E OF T.S. HANNA NEAR 29N71W AND EXTENDING S OVER THE CARIBBEAN. UPPER DIFFLUENCE TO THE E IS GENERATING SCATTERED SHOWERS/THUNDERSTORMS WITHIN 60 NM OF 69W BETWEEN 28N-32W. A SHEAR AXIS EXTENDS FROM THE E ATLC NEAR THE MADEIRA ISLANDS ALONG 32N29W THEN SW TO AN UPPER LOW CENTERED NEAR 19N45W CONTINUING OVER THE TROPICS TO 15N47W. UPPER DIFFLUENCE TO THE S IS ENHANCING THE CONVECTION ASSOCIATED WITH THE ITCZ. THE TYPICAL E/W UPPER RIDGE EXTENDS FROM OFF AFRICA ALONG 22N TO 40W AND S OF THE SHEAR AXIS. ADDITIONAL AT THE SURFACE IS A BROAD SURFACE RIDGE COVERING THE AREA N OF 20N E OF 55W AND N OF 30N E OF 70W ANCHORED N OF THE REGION. HANNA IS EXPECTED TO MOVE OUT OF THE REGION TONIGHT/SAT MORNING WITH IKE EFFECTING THE TURKS AND CAICOS BY SAT NIGHT/SUN. $$ WALLACE