WTPA45 PHFO 240850

TCDCP5



HURRICANE OLAF DISCUSSION NUMBER  38

NWS CENTRAL PACIFIC HURRICANE CENTER HONOLULU HI   EP192015

1100 PM HST FRI OCT 23 2015



THE DVORAK SUBJECTIVE ESTIMATES FROM HFO...JTWC AND SAB WERE ALL

5.5/102 KT...UNCHANGED FROM SIX HOURS AGO. THE UW-CIMSS OBJECTIVE

ESTIMATE WAS 5.9/112.4 KT. OLAF HAS MAINTAINED A RAGGED EYE OVER THE

PAST 6 HOURS. THE AREA OF COLD CLOUDS SURROUNDING THE CENTER HAS

BECOME A BIT MORE STRETCHED OUT TOWARDS THE NORTH. THE INITIAL

INTENSITY FOR THIS ADVISORY WILL BE KEPT AT 105 KT.



THE INITIAL MOTION FOR THIS ADVISORY IS EXPECTED TO CONTINUE 005/08

KT WITH GOOD CONFIDENCE IN RECENT CENTER POSITIONS. OLAF IS MOVING

THROUGH A WEAKNESS IN THE SUBTROPICAL RIDGE WITH A SHORT-WAVE TROUGH

PASSING EASTWARD FAR NORTH OF THE HURRICANE. OLAF IS FORECAST TO

CURVE SLIGHTLY TOWARD THE NORTHEAST WITH A SLIGHT SLOWING OF ITS

FORWARD MOTION OVER THE NEXT COUPLE OF DAYS...THEN START MOVING

FASTER TOWARD THE NORTHEAST. THE TRUSTED TRACK GUIDANCE IS IN GOOD

AGREEMENT FOR THE NEXT FEW DAYS. THE CURRENT FORECAST REMAINS CLOSE

TO THE GUIDANCE AND THE PREVIOUS TRACK.



SHIPS SHOWS 27 KT OF VERTICAL WIND SHEAR...VWS...FROM THE SOUTHWEST

WHILE UW-CIMSS SHOWS 36 KT FROM THE SOUTH SOUTHWEST. OLAF IS OVER 27

DEGREE CELSIUS WATER WITH THE SEA SURFACE TEMPERATURE...SST...

EXPECTED TO DROP SLIGHTLY TO 25.5 DEGREES ALONG THE FORECAST TRACK.

CONTINUING VWS AND DECREASING SST ARE EXPECTED TO STEADILY WEAKEN

OLAF OVER THE NEXT FEW DAYS.



THE FORECAST BECOMES MORE PROBLEMATICAL AFTER ABOUT 72 HOURS WHEN

THE GUIDANCE SHOWS THE SUBTROPICAL RIDGE BUILDING NORTH OF OLAF.

THAT CAN BE EXPECTED TO CAUSE OLAF TO TAKE A SHARP TURN TOWARD THE

WEST AND WEAKEN RAPIDLY. TIMING THE TURN TO THE WEST MAY BE

DIFFICULT SINCE THE TURN MAY BE QUITE SUDDEN AND SINCE THERE IS

QUITE A BIT OF SPREAD IN THE MODEL GUIDANCE REGARDING EXACTLY WHEN

AND WHERE IT WILL OCCUR. THE CURRENT FORECAST SHOWS THE TURN TAKING

PLACE WEDNESDAY MORNING...BUT THAT MAY NEED TO BE ADJUSTED IN LATER

FORECAST PACKAGES.







FORECAST POSITIONS AND MAX WINDS



INIT  24/0900Z 18.7N 145.6W  105 KT 120 MPH

 12H  24/1800Z 19.6N 145.1W   95 KT 110 MPH

 24H  25/0600Z 20.7N 144.4W   80 KT  90 MPH

 36H  25/1800Z 21.8N 143.7W   70 KT  80 MPH

 48H  26/0600Z 22.9N 142.8W   60 KT  70 MPH

 72H  27/0600Z 24.8N 140.2W   50 KT  60 MPH

 96H  28/0600Z 25.5N 139.5W   40 KT  45 MPH

120H  29/0600Z 26.0N 141.0W   30 KT  35 MPH



$$

FORECASTER DONALDSON