|
Show Selection: |
| #41720 (Received by flhurricane at: 10:46 PM 24.Aug.2005) TCDAT2 TROPICAL STORM KATRINA DISCUSSION NUMBER 6 NWS TPC/NATIONAL HURRICANE CENTER MIAMI FL 11 PM EDT WED AUG 24 2005 THE 2300Z RECONNAISSANCE FIX AND RADAR DATA FROM MIAMI AND THE BAHAMAS INDICATE THAT KATRINA HAS TURNED TOWARD THE WEST DURING THE LAST COUPLE OF HOURS. IT APPEARS THAT THE CYCLONE IS ALREADY SOUTH OF THE RIDGE AND EMBEDDED WITHIN WEAK STEERING CURRENTS. THIS PATTERN WOULD FORCE KATRINA TO MOVE VERY SLOWLY ON A GENERAL WESTWARD TRACK FOR THE NEXT 24 TO 48 HOURS. THIS MEANS THAT THE CYCLONE WILL LIKELY BE CROSSING THE SOUTHERN FLORIDA PENINSULA THURSDAY NIGHT AND ALL DAY FRIDAY. THIS IS CONSISTENT WITH THE RELIABLE DYNAMICAL GUIDANCE WHICH FOR THE FIRST TWO DAYS...BRINGS THE CYCLONE SLOWLY WESTWARD. BEYOND THREE DAYS...WHEN KATRINA IS FORECAST TO BE IN THE EASTERN GULF OF MEXICO...THE MODELS DIVERGE SIGNIFICANTLY...SUGGESTING TRACKS WHICH COVER THE COAST FROM MISSISSIPPI EASTWARD. THE OFFICIAL FORECAST TURNS KATRINA NORTHWARD OVER THE EASTERN GULF OF MEXICO AHEAD OF A STRONG APPROACHING TROUGH...ON A TRACK WHICH IS VERY CLOSE TO THE GLOBAL MODEL CONSENSUS. THIS FORECAST IS RATHER DIFFICULT SINCE ONE OF THE MORE RELIABLE MODELS...THE GFS...SHOWS THAT THE CYCLONE BARELY TOUCHES THE EAST COAST OF FLORIDA BEFORE MOVING NORTHWARD....WHILE THE OUTSTANDING GFDL MOVES KATRINA SOUTH OF DUE WEST ACROSS EXTREME SOUTH FLORIDA AND THE KEYS AS A VERY INTENSE HURRICANE. THE GFDL SCENARIO WOULD BE VERY DANGEROUS FOR SOUTH FLORIDA. THIS APPEARS TO BE UNREALISTIC AT THIS TIME BUT BECAUSE OF THE GOOD PAST PERFORMANCE OF THIS MODEL...WE MUST PAY CLOSE ATTENTION TO FUTURE MODEL RUNS. THE INITIAL INTENSITY HAS BEEN INCREASED TO 45 KNOTS BASED ON DVORAK ESTIMATES FROM ALL AGENCIES AND A BETTER RADAR PRESENTATION. LATEST RECONNAISSANCE DATA AT 2300 UTC DID NOT SHOW INTENSIFICATION AND THE PRESSURE WAS NOT DROPPING. HOWEVER...THE OFFICIAL INTENSITY FORECAST CALLS FOR A GRADUAL STRENGTHENING...AND MAKES KATRINA A CATEGORY ONE HURRICANE BEFORE LANDFALL...SINCE THERE IS LOW SHEAR AND HIGH SEA SURFACE TEMPERATURES ALONG KATRINA'S PATH. THE INTENSITY FORECAST FOLLOWS THE SHIPS MODEL BUT KATRINA COULD INTENSIFY A LITTLE MORE THAN ANTICIPATED. BECAUSE IT IS FORECAST THAT KATRINA BECOMES A HURRICANE BEFORE LANDFALL...A HURRICANE WARNING HAS BEEN ISSUED FOR A PORTION OF THE EAST FLORIDA COAST. FORECASTER AVILA FORECAST POSITIONS AND MAX WINDS INITIAL 25/0300Z 26.0N 78.0W 45 KT 12HR VT 25/1200Z 26.0N 78.8W 55 KT 24HR VT 26/0000Z 26.0N 79.5W 65 KT 36HR VT 26/1200Z 26.0N 80.5W 50 KT...INLAND 48HR VT 27/0000Z 26.3N 81.5W 40 KT...INLAND 72HR VT 28/0000Z 27.0N 83.0W 50 KT...OVER WATER 96HR VT 29/0000Z 29.0N 85.0W 70 KT 120HR VT 30/0000Z 32.0N 84.0W 30 KT...INLAND |
