000
WTNT42 KNHC 012040
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