WTPA45 PHFO 260237

TCDCP5



HURRICANE OLAF DISCUSSION NUMBER  45

NWS CENTRAL PACIFIC HURRICANE CENTER HONOLULU HI   EP192015

500 PM HST SUN OCT 25 2015



THE SATELLITE REPRESENTATION OF OLAF HAS BEGUN TO DETERIORATE AS

STRONG WESTERLY SHEAR IMPACTS THE SYSTEM. SUBJECTIVE DVORAK CURRENT

INTENSITY ESTIMATES ARE 4.0/65 KT FROM PHFO AND JTWC AND 4.5/77 KT

FROM SAB. BASED ON THESE FIXES ALONG WITH ITS RECENT APPEARANCE IN

SATELLITE IMAGERY...HAVE LOWERED THE INITIAL INTENSITY TO 70 KT WITH

THIS ADVISORY PACKAGE. A 0058Z SSMIS PASS CONTINUES TO INDICATE A

TILTED SYSTEM WITH THE LOW LEVEL CENTER LOCATED TO THE WEST OF THE

MID AND UPPER LEVEL CIRCULATION.



OLAF IS MOVING TOWARD THE NORTHEAST BETWEEN AN EAST TO WEST ORIENTED

RIDGE CENTERED TO THE SOUTHEAST OF THE SYSTEM AND A DIGGING UPPER

LEVEL TROUGH TO ITS NORTHWEST. THE UPPER LEVEL TROUGH IS

BECOMING THE DOMINANT STEERING MECHANISM AND WILL CONTINUE TO

INFLUENCE OLAF DURING THE NEXT COUPLE OF DAYS. THE UPPER TROUGH

WILL CONTINUE TO MOVE OLAF TOWARD THE NORTHEAST THROUGH ABOUT 48

HOURS. BEYOND 48 HOURS A MUCH WEAKER AND SLOWER MOVING OLAF WILL

COME UNDER THE INFLUENCE OF A LOW LEVEL RIDGE BUILDING IN TO ITS

NORTHWEST. A RATHER SHARP TURN TO THE RIGHT IS FORECAST BY MOST OF

THE MODEL GUIDANCE BEYOND 48 HOURS WITH THE GFS REMAINING AN OUTLIER

DUE TO KEEPING OLAF AS A STRONGER SYSTEM AT THAT TIME.



THE LATEST INTENSITY FORECAST HAS BEEN ADJUSTED SLIGHTLY LOWER FROM

THE PREVIOUS ADVISORY PACKAGE DUE TO THE INITIAL WEAKENING TREND

OBSERVED IN SATELLITE IMAGERY. OLAF IS CURRENTLY EXPERIENCING

20 TO 30 KT OF WESTERLY SHEAR. SHIPS GUIDANCE KEEPS HIGH SHEAR

VALUES OVER THE SYSTEM DURING THE NEXT SEVERAL DAYS. THIS ALONG WITH

COOLER SST VALUES ALONG ITS PATH WILL RESULT IN GRADUAL WEAKENING AS

INDICATED BY ALL OF THE INTENSITY GUIDANCE. OLAF IS EXPECTED TO

WEAKEN TO A TROPICAL STORM TONIGHT OR MONDAY MORNING AND TO A

DEPRESSION BY 72 HOURS. BY DAY 4 WE EXPECT OLAF TO BECOME VOID OF

DEEP CONVECTION WITH JUST A SHALLOW LOW EXPECTED WITH DISSIPATION

FORECAST BY DAY 5. THIS FOLLOWS CLOSELY ALONG WITH MOST OF THE

RELIABLE MODEL GUIDANCE.



FORECAST POSITIONS AND MAX WINDS



INIT  26/0300Z 23.5N 142.5W   70 KT  80 MPH

 12H  26/1200Z 25.0N 141.0W   60 KT  70 MPH

 24H  27/0000Z 26.5N 138.4W   50 KT  60 MPH

 36H  27/1200Z 28.0N 135.7W   40 KT  45 MPH

 48H  28/0000Z 28.6N 133.4W   35 KT  40 MPH

 72H  29/0000Z 28.1N 132.1W   25 KT  30 MPH

 96H  30/0000Z 27.0N 132.6W   20 KT  25 MPH...POST-TROP/REMNT LOW

120H  31/0000Z...DISSIPATED



$$

FORECASTER BURKE