000 WTPZ43 KNHC 022032 TCDEP3 TROPICAL STORM OLAF DISCUSSION NUMBER 6 NWS TPC/NATIONAL HURRICANE CENTER MIAMI FL EP182009 200 PM PDT FRI OCT 02 2009 SATELLITE IMAGERY SHOWS THAT CLOUD TOPS HAVE WARMED IN ASSOCIATION WITH OLAF OVER THE PAST FEW HOURS...AS THE SSTS OF LESS THAN 25C ARE TAKING A TOLL ON THE CYCLONE. ALSO...THE LOW-LEVEL CIRCULATION CENTER APPEARS TO BE DECOUPLING FROM THE MID-LEVEL CIRCULATION... LIKELY DUE TO THE 15-20 KNOTS OF SOUTHWESTERLY SHEAR SEEN IN ANALYSES FROM UW-CIMSS. GIVEN THE DEGRADED SATELLITE APPEARANCE... THE INITIAL INTENSITY IS LOWERED TO 35 KT. THIS IS IN AGREEMENT WITH DVORAK CI-NUMBERS FROM TAFB AND SAB AND A 32-KT WIND OBSERVED BY SHIP 3FXY2 ABOUT 150 MILES NORTH OF THE CENTER AT 1800 UTC. FURTHER WEAKENING IS EXPECTED DUE TO COOL WATERS AND THE SHEAR INCREASING TO MORE THAN 30 KT IN 24 HOURS...AS INDICATED BY THE SHIPS MODEL. THE OFFICIAL FORECAST IS IN CLOSE AGREEMENT WITH THE ICON INTENSITY CONSENSUS...AND SHOWS OLAF BECOMING A REMNANT LOW BY 36 HOURS AND DISSIPATING BY 48 HOURS...ALTHOUGH THIS COULD OCCUR SOONER. THE INITIAL MOTION ESTIMATE IS 010/08...A LITTLE TO THE RIGHT OF PREVIOUS ESTIMATES AND THE PREVIOUS FORECAST. THE MODEL GUIDANCE IS IN GOOD AGREEMENT ON THE OVERALL TRACK SCENARIO...WITH OLAF TURNING TOWARD THE NORTHEAST AND EAST-NORTHEAST AHEAD OF A MID-LEVEL TROUGH APPROACHING THE CALIFORNIA COAST IN THE NEXT DAY OR SO. THE TRACK FORECAST IS ADJUSTED TOWARD THE NEW MODEL CONSENSUS...BUT IS SLOWER THAN MOST OF THE GUIDANCE BASED ON THE ASSUMPTION THAT THE LOW-LEVEL CIRCULATION WILL CONTINUE TO DECOUPLE. WHAT IS LEFT OF THE CIRCULATION SHOULD DISSIPATE OVER THE RUGGED TERRAIN OF THE BAJA PENINSULA BY 48 HOURS. RAINFALL ASSOCIATED WITH OLAF WILL SPREAD INTO CENTRAL PORTIONS OF THE BAJA PENINSULA TONIGHT AND SATURDAY. FORECAST POSITIONS AND MAX WINDS INITIAL 02/2100Z 23.8N 117.2W 35 KT 12HR VT 03/0600Z 24.8N 116.7W 30 KT 24HR VT 03/1800Z 26.0N 115.4W 25 KT 36HR VT 04/0600Z 27.0N 113.4W 20 KT...REMNANT LOW 48HR VT 04/1800Z...DISSIPATED $$ FORECASTER BRENNAN