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2024's Atlantic name list reuses 2018s, with Milton replacing Michael, and Francine Replacing Florence.
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| #4354 (Received by flhurricane at: 10:42 PM 11.Aug.2004) TCDAT2 TROPICAL STORM BONNIE DISCUSSION NUMBER 16 NWS TPC/NATIONAL HURRICANE CENTER MIAMI FL 11 PM EDT WED AUG 11 2004 BONNIE HAS UNDERGONE SIGNIFICANT STRUCTURAL CHANGES DURING THE PAST 6-9 HR. THE TIGHT INNER CORE THAT HAD BEEN PRESENT FOR THE LAST THREE DAYS COLLAPSED DURING THE AFTERNOON...LEAVING THE MAXIMUM WINDS IN A BAND OF CONVECTION AWAY FROM THE CENTER. SO FAR...THE EVENING RECONNAISSANCE FLIGHT HAS REPORTED A CENTRAL PRESSURE OF 1007-1008 MB AND MAXIMUM 850 MB FLIGHT LEVEL WINDS OF 39 KT. ON THE OTHER HAND...SATELLITE INTENSITY ESTIMATES ARE 55 KT FROM TAFB AND 45 KT FROM SAB AND AFWA...SUGGESTING THE AIRCRAFT MIGHT NOT HAVE SAMPLED THE STRONGEST WINDS. THE INITIAL INTENSITY IS DECREASED TO 50 KT...AND THIS MAY BE GENEROUS. THE INITIAL MOTION IS 045/10. THE TRACK FORECAST IS VERY STRAIGHT FORWARD. BONNIE IS BECOMING EMBEDDED IN SOUTHWESTELY FLOW ASSOCIATED WITH AN UNSEASONABLY STRONG DEEP LAYER TROUGH OVER THE CENTRAL UNITED STATES. THE CYCLONE SHOULD ACCELERATE NORTHEASTWARD ON THE EAST SIDE OF THE TROUGH...MAKING LANDFALL OVER THE FLORIDA PANHANDLE THURSDAY MORNING AND THEN MOVING THROUGH THE EASTERN UNITED STATES. ALL TRACK GUIDANCE AGREES WITH THIS SCENARIO...AND THE TRACK FORECAST IS AN UPDATE OF THE PREVIOUS PACKAGE. THE COLLAPSE OF THE CENTRAL CORE AND STEADILY INCREASING VERTICAL SHEAR SUGGESTS THAT THE WINDOW OF OPPORTUNITY FOR STRENGTHENING IS CLOSING. HOWEVER...THE CYCLONE HAS JUST GENERATED A BURST OF CONVECTION NORTHEAST OF THE CENTER...AND A REPEAT OF LAST NIGHTS FLARE-UP COULD REGENERATE A TIGHT CENTER AND BRING BONNIE TO HURRICANE STRENGTH. ON THE OTHER HAND...IT MIGHT NOT STRENGTHEN AT ALL BEFORE LANDFALL. THE INTENSITY FORECAST WILL COMPROMISE BETWEEN THESE EXTREMES AND CALL FOR GRADUAL STRENGTHENING PRIOR TO LANDFALL. AFTER LANDFALL... BONNIE SHOULD WEAKEN AND BECOME EXTRATROPICAL. ONE CHANGE TO THE PREVIOUS FORECAST IS TO KEEP THE WINDS AT 35 KT DURING THE EXTRATROPICAL STAGE DUE TO THE NEAR 35 KT MOTION. SINCE BONNIE COULD STILL REACH HURRICANE STRENGTH DURING THE DIURNAL CONVECTIVE MAXIMUM...THE HURRICANE WARNING WILL REMAIN IN EFFECT. THIS WARNING COULD BE DISCONTINUED IF LATER DATA SHOWS THAT BONNIE IS NOT RE-INTENSIFYING. FORECASTER BEVEN FORECAST POSITIONS AND MAX WINDS INITIAL 12/0300Z 27.4N 88.4W 50 KT 12HR VT 12/1200Z 28.9N 86.8W 60 KT 24HR VT 13/0000Z 31.9N 83.6W 45 KT...INLAND 36HR VT 13/1200Z 36.5N 78.5W 35 KT...INLAND EXTRATROPICAL 48HR VT 14/0000Z 42.0N 73.5W 35 KT...INLAND EXTRATROPICAL 72HR VT 15/0000Z 53.5N 62.0W 35 KT...INLAND EXTRATROPICAL 96HR VT 16/0000Z...ABSORBED BY FRONTAL ZONE |
