|
Show Selection: |
| #539384 (Received by flhurricane at: 4:41 PM 01.Sep.2012) TCDAT2 TROPICAL STORM LESLIE DISCUSSION NUMBER 10 NWS NATIONAL HURRICANE CENTER MIAMI FL AL122012 500 PM AST SAT SEP 01 2012 SATELLITE IMAGES SHOW THAT THE CENTER OF LESLIE IS EXPOSED TO THE NORTHWEST OF A WEAKENING CONVECTIVE CLUSTER. INTENSITY ESTIMATES ARE DROPPING...SO THE INITIAL WINDS ARE REDUCED TO 55 KT. NORTHWESTERLY SHEAR IS FORECAST TO PERSIST AND SOMEWHAT INCREASE OVER THE NEXT COUPLE OF DAYS PRIMARILY DUE TO FLOW AROUND THE EASTERN PORTION OF AN UPPER-LEVEL HIGH. CURIOUSLY...THE MODELS DO NOT WEAKEN THE SYSTEM MUCH MORE...PERHAPS BECAUSE LESLIE MOVES THROUGH AN EXTREMELY UNSTABLE ENVIRONMENT AND WARM WATERS. THE NHC FORECAST IS REDUCED FROM THE PREVIOUS ONE...SHOWING A STEADY STATE CYCLONE FOR THE NEXT COUPLE OF DAYS...BUT IT WOULD NOT BE SURPRISING IF LESLIE WEAKENED SOMEWHAT DURING THAT TIME. THE NEW FORECAST STILL LEAVES OPEN THE CHANCE THAT CYCLONE WILL RECOVER IN A FEW DAYS TIME DUE TO A POSSIBLE LESSENING OF THE SHEAR. VISIBLE FIXES GIVE A MOTION OF ABOUT 295/16. THERE IS NO CHANGE TO THE SYNOPTIC REASONING AS LESLIE SHOULD TURN TO THE NORTHWEST BY LATE TOMORROW AS IT MOVES AROUND A WEAKENING RIDGE OVER THE CENTRAL ATLANTIC OCEAN. THE GLOBAL MOTION ARE THEN CONSISTENT ABOUT THE CYCLONE TURNING BY EARLY TUESDAY DUE TO A BREAK IN THE RIDGE. THE NEW NHC FORECAST CONTINUES TO SHIFT THE TRACK A BIT FASTER AND LEFT OF THE PREVIOUS ONE THROUGH THE FIRST FEW DAYS. THE LONG RANGE FORECAST IS UNCERTAIN BECAUSE IT INVOLVES THE INTERACTION OF MANY FEATURES...INCLUDING THE REMNANTS OF ISAAC...A CUTOFF LOW OFFSHORE OF FLORIDA...AND A WEAK RIDGE OVER THE CENTRAL ATLANTIC. GIVEN THE UNCERTAINTY...THE OFFICIAL FORECAST IS TRENDED TOWARD THE MODEL CONSENSUS...WHICH ENDS UP BEING A BIT SLOWER AND WEST OF THE PREVIOUS FORECAST. FORECAST POSITIONS AND MAX WINDS INIT 01/2100Z 19.2N 57.3W 55 KT 65 MPH 12H 02/0600Z 20.3N 59.2W 55 KT 65 MPH 24H 02/1800Z 21.9N 61.0W 55 KT 65 MPH 36H 03/0600Z 23.6N 62.2W 55 KT 65 MPH 48H 03/1800Z 24.9N 62.8W 55 KT 65 MPH 72H 04/1800Z 26.3N 62.9W 60 KT 70 MPH 96H 05/1800Z 27.5N 62.5W 65 KT 75 MPH 120H 06/1800Z 29.0N 62.5W 70 KT 80 MPH $$ FORECASTER BLAKE |
