000 AXNT20 KNHC 060003 TWDAT TROPICAL WEATHER DISCUSSION NWS TPC/NATIONAL HURRICANE CENTER MIAMI FL 805 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 1800 UTC SURFACE ANALYSIS AND SATELLITE IMAGERY THROUGH 2315 UTC. ...SPECIAL FEATURES... TROPICAL STORM HANNA IS CENTERED NEAR 31.6N 79.3W AT 06/0000 UTC OR ABOUT 85 NM SOUTH-SOUTHEAST OF CHARLESTON SOUTH CAROLINA AND ABOUT 170 NM SOUTH-SOUTHWEST OF WILMINGTON NORTH CAROLINA MOVING N AT 17 KT. THE LATEST MINIMUM CENTRAL PRESSURE REPORTED BY AN AIR FORCE RESERVE 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 PROVIDING SHEAR OVER HANNA AND COUPLED WITH DRY AIR ARE LIMITING CONVECTION IN THE SRN SEMICIRCLE. HANNA STILL REMAINS A STRONG TROPICAL STORM AND WILL CONTINUE TO MOVE NORTHWARD WITH A TURN TO THE NE EXPECTED ON SATURDAY AS IT TRACKS OVER THE SOUTHEASTERN AND MID-ATLC COAST OF THE US. SCATTERED MODERATE/STRONG CONVECTION IS FROM 30N-33N BETWEEN 78W-80W WITH SCATTERED SHOWERS/TSTMS COVERING THE REMAINDER OF THE AREA N OF 30N TO BEYOND 32N W OF 76W TO INLAND OVER THE SE US...INCLUDING FAR NE FLORIDA. HURRICANE IKE IS CENTERED NEAR 22.8N 64.7W AT 06/0000 UTC OR ABOUT 270 NM NORTH-NORTHEAST OF SAN JUAN PUERTO RICO AND ABOUT 365 NM EAST OF GRAND TURK ISLAND MOVING W-SW AT 13 KT. ESTIMATED MINIMUM CENTRAL PRESSURE IS 958 MB. MAXIMUM SUSTAINED WIND SPEED IS 100 KT WITH GUSTS TO 120 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 AS IT TRACKS ALONG THE SRN PERIPHERY OF A W ATLC UPPER HIGH. NUMEROUS MODERATE/STRONG CONVECTION IS WITHIN 100 NM OF THE CENTER IN ALL QUADRANTS WITH SCATTERED SHOWERS AND TSTMS COVERING THE REMAINDER OF THE AREA FROM 18N-25N BETWEEN 62W-67W. TROPICAL STORM JOSEPHINE IS CENTERED NEAR 16.0N 35.2W AT 05/2100 UTC OR ABOUT 630 NM WEST OF THE SOUTHERNMOST CAPE VERDE ISLANDS MOVING NW AT 7 KT. ESTIMATED MINIMUM CENTRAL PRESSURE IS 1004 MB. MAXIMUM SUSTAINED WIND SPEED IS 35 KT WITH GUSTS TO 45 KT. SEE LATEST NHC FORECAST/ADVISORY UNDER AWIPS/WMO HEADERS MIATCMAT5/WTNT25 KNHC FOR MORE DETAILS. STRONG SOUTHERLY UPPER SHEAR HAVE COMPLETELY EXPOSED THE LOW LEVEL CENTER OF JOSEPHINE WITH NO REMAINING DEEP CONVECTION. THIS SHEAR IS EXPECTED TO REMAIN OVER THE AREA FOR THE NEXT COUPLE OF DAYS AND THEN WEAKEN. THEREFORE IF THE LOW CENTER REMAINS INTACT...JOSEPHINE COULD RESTRENGTHEN THEREAFTER. SCATTERED SHOWERS AND POSSIBLE ISOLATED TSTMS ARE FROM 16N-21N BETWEEN 30W-38W. ...TROPICAL WAVES... TROPICAL WAVE IS OVER THE WRN CAPE VERDE ISLANDS ALONG 25W S OF 19N MOVING W 10-15 KT. WEAK CURVATURE IS OBSERVED ON SATELLITE IMAGERY WITH A SMALL AREA OF SCATTERED MODERATE CONVECTION FROM 10N-13N BETWEEN 25W-27W. TROPICAL WAVE IS ALONG 55W S OF 15N MOVING W NEAR 15 KT. WAVE REMAINS LOW AMPLITUDE AND APPEAR EMBEDDED WITHIN THE ITCZ. SCATTERED MODERATE/ISOLATED STRONG CONVECTION IS FROM 9N-13N BETWEEN 53W-58W. ...THE ITCZ... THE ITCZ AXIS IS ANALYZED ALONG 13N15W 14N23W 11N39W 9N52W... DISRUPTED BY THE TWO TROPICAL WAVES AND T.S. JOSEPHINE. NUMEROUS STRONG CONVECTION IS ALONG THE W AFRICA COAST FROM 10N-15N BETWEEN 9W-17W. SCATTERED MODERATE CONVECTION IS FROM 4N-7N BETWEEN 25W-28W. CLUSTERS OF SCATTERED MODERATE/ISOLATED STRONG CONVECTION IS FROM 9N-14N BETWEEN 45W-58W. ...DISCUSSION... GULF OF MEXICO... A BROAD UPPER LONGWAVE TROUGH IS OVER THE CENTRAL CONUS INTO THE NW GULF WITH A STATIONARY FRONT ENTERING THE GULF ALONG THE WRN MISSISSIPPI COAST EXTENDING SW TO NEAR 26N94W. A WEAK INVERTED UPPER TROUGH EXTENDS FROM THE COAST OF SRN MEXICO IN THE BAY OF CAMPECHE TO THE NE GULF. A SURFACE TROUGH PARALLELS THE E/CENTRAL MEXICO COAST FROM 23N96W TO NEAR XALAPA MEXICO GENERATING SCATTERED SHOWERS/ISOLATED TSTMS FROM 20N-26N W OF 96W. AN UPPER RIDGE IS CENTERED IN THE W ATLC AND COVERS THE FLORIDA PENINSULA. MULTILAYERED OUTFLOW CLOUDINESS FROM T.S. HANNA IS ACROSS THE ERN GULF E OF 90W ROTATING AROUND THE AFOREMENTIONED UPPER TROUGH CENTERED NORTH OF THE YUCATAN PENINSULA. CARIBBEAN SEA... BROAD UPPER LEVEL RIDGE DOMINATES THE CARIBBEAN ANCHORED IN THE W ATLC E OF T.S. HANNA CENTERED NEAR 27N74W. UPPER DIFFLUENCE IS GENERATING ISOLATED SHOWERS ACROSS THE NW CARIBBEAN BETWEEN CUBA AND THE CAYMAN ISLANDS FROM 18N-21N BETWEEN 76W-81W. SCATTERED SHOWERS/TSTMS ALSO COVER HONDURAS AND THE ADJACENT NRN COAST S OF 17N BETWEEN 84W-90W. STRONG SUBSIDENCE/DRY AIR IS NOTED MOVING ACROSS THE SRN CARIBBEAN S OF 16N BETWEEN 63W-79W. MULTILAYERED CLOUDINESS AND POSSIBLE SCATTERED SHOWERS ARE ACROSS THE NE CARIBBEAN AS OUTFLOW STREAMS SW FROM HURRICANE IKE ACROSS PUERTO RICO AND THE MONA PASSAGE. 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 27N74W AND EXTENDING S OVER MUCH OF THE CARIBBEAN SEA. A SHEAR AXIS EXTENDS FROM THE ERN ATLC W OF THE MADEIRA ISLANDS ALONG 32N31W THEN SW TO AN UPPER LOW CENTERED NEAR 19N46W CONTINUING OVER THE TROPICS TO 13N51W. UPPER DIFFLUENCE E OF THE CENTRAL ATLC UPPER LOW IS ENHANCING THE CONVECTION ASSOCIATED WITH THE ITCZ BETWEEN 45W-58W. AN E/W UPPER RIDGE EXTENDS FROM W AFRICA ALONG 22N TO 40W AND S OF 30N. AT THE SURFACE...A BROAD SURFACE RIDGE COVERS THE AREA N OF 23N E OF 55W AND N OF 30N E OF 70W ANCHORED N OF THE REGION. HANNA IS EXPECTED TO MOVE NORTH OF THE REGION TONIGHT/SAT MORNING WITH IKE EFFECTING THE TURKS AND CAICOS BY SAT NIGHT/SUN. $$ HUFFMAN