000 AXNT20 KNHC 011203 TWDAT TROPICAL WEATHER DISCUSSION NWS TPC/NATIONAL HURRICANE CENTER MIAMI FL 805 AM EDT MON SEP 01 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... HURRICANE GUSTAV IS CENTERED NEAR 28.8N 90.1W AT 01/1100 UTC OR ABOUT 75 NM SOUTH OF NEW ORLEANS LOUISIANA MOVING NW AT 14 KT. ESTIMATED MINIMUM CENTRAL PRESSURE IS 954 MB. MAXIMUM SUSTAINED WIND SPEED IS 100 KT WITH GUSTS TO 120 KT. SEE LATEST NHC FORECAST/ADVISORY UNDER AWIPS/WMO HEADERS MIATCMAT2/WTNT22 KNHC FOR MORE DETAILS. GUSTAV'S CORE OF CONVECTION HAS BECOME MORE SYMMETRICAL AND A LARGE FEEDER BAND IS N OF THE CENTER. STORM INTENSITY IS STEADY AS IT APPROACHES THE LOUISIANA COAST. A DANGEROUS STORM SURGE OF 10 TO 14 FEET ABOVE NORMAL TIDAL LEVELS IS EXPECTED NEAR AND TO THE EAST OF WHERE THE CENTER OF GUSTAV CROSSES THE COAST. NUMEROUS STRONG CONVECTION IS NEAR THE CENTER FROM 27N-30N BETWEEN 89W-91W. IN ADDITION...SCATTERED MODERATE CONVECTION IS N OF THE CENTER FROM 30N-32N BETWEEN 85W-92W DUE TO A FEEDER BAND. TROPICAL STORM HANNA IS CENTERED NEAR 23.6N 72.4W AT 01/1100 UTC OR ABOUT 90 MILES NORTH-NORTHEAST OF THE SOUTHEASTERN BAHAMAS MOVING W AT 2 KT. ESTIMATED MINIMUM CENTRAL PRESSURE IS 996 MB. MAXIMUM SUSTAINED WIND SPEED IS 45 KT WITH GUSTS TO 55 KT. SEE LATEST NHC FORECAST/ADVISORY UNDER AWIPS/WMO HEADERS MIATCMAT3/WTNT23 KNHC FOR MORE DETAILS. HANNA IS EXPERIENCING NORTHERLY SHEAR AND THIS WILL INHIBIT SIGNIFICANT STRENGTHENING OVER THE NEXT TWO DAYS. THE STORM IS BEING STEERED BY A MIDDLE/UPPER LEVEL RIDGE OVER THE WESTERN ATLANTIC. CONVECTION IS MOSTLY S OF THE CENTER. NUMEROUS STRONG CONVECTION IS FROM 20N-24N BETWEEN 68W-73W. IN ADDITION... SCATTERED MODERATE CONVECTION IS FROM 19N-24N BETWEEN 68W-74W TO INCLUDE THE SOUTHERN BAHAMAS. A TROPICAL WAVE IS ALONG 37W/38 FROM 10N TO 23N WITH AN EMBEDDED 1006 MB SURFACE LOW ALONG THE WAVE AXIS AT 17N. THE WAVE HAS THE POTENTIAL TO DEVELOP INTO A TROPICAL CYCLONE OVER THE NEXT 24 HOURS. ANTICYCLONIC FLOW ALOFT IS ALREADY OVER THE SURFACE LOW. THE WAVE IS MOVING W 10-15 KT. THE SURFACE CIRCULATION ALSO COVERS A LARGE AREA. SCATTERED MODERATE TO STRONG CONVECTION FROM 16N-20N BETWEEN 35W-41W. ...TROPICAL WAVES... A TROPICAL WAVE IS OFF THE COAST OF WEST AFRICA ALONG 19W FROM 7N TO 16N. IT IS MOVING W AT 10 KT. SCATTERED MODERATE TO STRONG CONVECTION IS FROM 9N-16N BETWEEN 17W-22W. A TROPICAL WAVE IS ALONG 52W FROM 15N TO 27N WITH AN EMBEDDED 1008 MB SURFACE LOW ALONG THE WAVE AXIS AT 22N. THE WAVE IS MOVING WNW ABOUT 10 KT AND THE LOW IS DEFINED BY A SWIRL OF LOW LEVEL CLOUDS. WINDS ALOFT DO NOT SUPPORT TROPICAL CYCLONE DEVELOPMENT. SCATTERED MODERATE TO ISOLATED STRONG CONVECTION IS N OF THE WAVE AXIS FROM 26N-31N BETWEEN 49W-53W. ...THE ITCZ... THE ITCZ AXIS IS ANALYZED ALONG 11N15W 9N19W 17N37W 11N40W 13N55W 13N61W. BESIDES THE CONVECTION MENTIONED IN THE TROPICAL WAVE SECTION...ISOLATED MODERATE CONVECTION IS FROM 6N-10N BETWEEN 36W-44W. ...DISCUSSION... GULF OF MEXICO... HURRICANE GUSTAV IS IN THE PROCESS OF MAKING LANDFALL ON THE LOUISIANA COAST THIS MORNING AS A MAJOR HURRICANE. THE CENTRAL CORE CONVECTION IS ALREADY OVER LAND...AS IS THE NORTHERN FEEDER BAND. SEE SPECIAL FEATURES ABOVE. OVERCAST SKIES ARE OVER THE N GULF N OF 25N. MOSTLY FAIR WEATHER IS OVER THE SW GULF AND THE BAY OF CAMPECHE. IN THE UPPER LEVELS...UPPER LEVEL ANTICYCLONIC OUTFLOW FROM GUSTAV COVERS THE ENTIRE GULF. CARIBBEAN SEA... FRESH TRADEWINDS DOMINATE THE CARIBBEAN SEA. SCATTERED MODERATE CONVECTION IS INLAND OVER N COLOMBIA FROM 6N-10N BETWEEN 71W-77W. SIMILAR CONVECTION IS INLAND OVER INLAND BELIZE AND GUATEMALA. IN THE UPPER LEVELS...MOSTLY EASTERLY FLOW IS NOTED OVER THE CARIBBEAN. SUBSIDENCE AND DRY AIR IS OVER THE CENTRAL CARIBBEAN BETWEEN 64W-74W. CONSIDERABLE UPPER LEVEL MOISTURE IS OVER THE REMAINDER OF THE CARIBBEAN AND CENTRAL AMERICA. ATLANTIC OCEAN... A 1025 MB HIGH IS OVER THE EASTERN ATLANTIC NEAR 33N30W. T.S. HANNA AND THE TROPICAL WAVES ARE THE MAIN FEATURES IN THE TROPICAL ATLANTIC. SEE ABOVE. IN THE UPPER LEVELS...AN UPPER LEVEL LOW IS OVER THE CENTRAL ATLANTIC NEAR 27N52W. AN UPPER LEVEL HIGH IS OVER THE E ATLANTIC NEAR 30N40W.` $$ FORMOSA