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#451236 (Received by flhurricane at: 10:52 AM 19.Aug.2011) TCDAT3 TROPICAL DEPRESSION EIGHT DISCUSSION NUMBER 3 NWS NATIONAL HURRICANE CENTER MIAMI FL AL082011 1100 AM EDT FRI AUG 19 2011 AN AIR FORCE RESERVE HURRICANE HUNTER AIRCRAFT FOUND THAT THE WELL-DEFINED CENTER OF TROPICAL DEPRESSION EIGHT WAS ABOUT 30 N MI NORTHEAST OF THE POSITION IN EARLIER ADVISORIES. HOW MUCH OF THIS SHIFT IS DUE TO A CHANGE IN THE MOTION AND HOW MUCH IS DUE TO REFORMATION OF THE CENTER IS NOT OBVIOUS IN THE DATA CURRENTLY AVAILABLE. THE AIRCRAFT HAS REPORTED CENTRAL PRESSURES OF 1004-1005 MB...850 MB FLIGHT-LEVEL WINDS OF 40 KT...AND RELIABLE SFMR SURFACE WIND ESTIMATES OF 30-35 KT. THESE DATA SUGGEST THAT THE CYCLONE IS JUST BELOW TROPICAL-STORM STRENGTH...AND THE INITIAL INTENSITY REMAINS 30 KT. THE INITIAL MOTION IS A RATHER UNCERTAIN 275/9. A LOW/MID-LEVEL RIDGE OVER THE GULF OF MEXICO AND THE NORTHERN GULF COAST IS EXPECTED TO GRADUALLY STRENGTHEN DURING THE NEXT 48-72 HR...AND THIS SHOULD STEER THE CYCLONE GENERALLY WESTWARD TO WEST- NORTHWESTWARD THROUGH ITS LIFETIME. THE NEW FORECAST TRACK IS PARALLEL TO...BUT SHIFTED NORTH OF...THE PREVIOUS FORECAST AND LIES NEAR THE CENTER OF THE TRACK GUIDANCE ENVELOPE. THE FORECAST TRACK HAS THE CENTER PASSING NEAR THE BAY ISLANDS OF HONDURAS TONIGHT AND OVER THE COAST OF BELIZE SATURDAY OR SATURDAY NIGHT. THE NEW FORECAST TRACK ALLOWS THE CYCLONE TO SPEND MORE TIME OVER WATER THAN PREVIOUSLY EXPECTED...AND THIS REQUIRES REVISING THE INTENSITY FORECAST UPWARD. THE NEW INTENSITY FORECAST CALLS FOR THE SYSTEM TO BECOME A TROPICAL STORM IN 12 HR OR LESS AND TO REACH A PEAK INTENSITY OF 45 KT NEAR THE TIME OF LANDFALL IN BELIZE. THIS FORECAST IS A COMPROMISE BETWEEN THE WEAKER GFDL/HWRF MODELS AND THE STRONGER SHIPS/LGEM MODELS. THE NEW FORECAST REQUIRES SIGNIFICANT CHANGES TO THE WATCHES AND WARNINGS AT THIS TIME. FORECAST POSITIONS AND MAX WINDS INIT 19/1500Z 16.1N 83.7W 30 KT 35 MPH 12H 20/0000Z 16.3N 85.0W 35 KT 40 MPH 24H 20/1200Z 16.7N 86.8W 40 KT 45 MPH 36H 21/0000Z 17.1N 88.6W 45 KT 50 MPH...INLAND 48H 21/1200Z 17.5N 90.5W 30 KT 35 MPH...INLAND 72H 22/1200Z 18.0N 94.5W 20 KT 25 MPH...POST-TROP/REMNT LOW 96H 23/1200Z...DISSIPATED $$ FORECASTER BEVEN |