ZCZC MIATCDAT5 ALL TTAA00 KNHC DDHHMM HURRICANE JEANNE DISCUSSION NUMBER 18 NATIONAL WEATHER SERVICE MIAMI FL 11 PM EDT FRI SEP 25 1998 JEANNE HAS CONTINUED TO LOOK RAGGED ON IR SATELLITE IMAGERY AND DVORAK CI NUMBERS ARE 4.5. THEREFORE THE INTENSITY IS ESTIMATED AT 75 KNOTS. WATER VAPOR IMAGERY INDICATES THAT THE STORM IS BEING SHEARED BY AN UPPER LEVEL TROUGH. HOWEVER THE SHIPS INTENSITY MODEL AND THE GFDL MODEL CONTINUE TO SUGGEST THAT THE STORM WILL REMAIN A HURRICANE THROUGH 72 HOURS. IF THE SHEAR RELAXES IN THE NEXT DAY OR SO...AS SUGGESTED BY THE EVOLUTION OF THE UPPER LEVEL TROUGH IN THE AVN FORECAST...STRENGTHENING MIGHT STILL BE POSSIBLE. AS A COMPROMISE...THE INTENSITY IS HELD CONSTANT THROUGH 72 HOURS. ALL OF THE TRACK GUIDANCE MODELS INDICATE A GENERAL NORTHWARD MOTION FOR THE NEXT SEVERAL DAYS. THE CURRENT MOTION IS 325/9 KNOTS...BUT AN INCREASE IN FORWARD SPEED IS EXPECTED. THE OFFICIAL FORECAST IS SHIFTED A LITTLE TO THE EAST OF THE PREVIOUS FORECAST...SINCE THE GFDL...UKMET...AND LBAR MODELS INDICATE A NORTH NORTHEAST MOTION AFTER 48 HOURS. DEMARIA FORECAST POSITIONS AND MAX WINDS INITIAL 26/0300Z 20.5N 39.4W 75 KTS 12HR VT 26/1200Z 21.6N 40.2W 75 KTS 24HR VT 27/0000Z 23.4N 40.9W 75 KTS 36HR VT 27/1200Z 25.8N 41.1W 75 KTS 48HR VT 28/0000Z 28.8N 40.8W 75 KTS 72HR VT 29/0000Z 37.2N 38.3W 75 KTS NNNN