WTPA35 PHFO 241438
TCPCP5

BULLETIN
HURRICANE OLAF ADVISORY NUMBER 39
NWS CENTRAL PACIFIC HURRICANE CENTER HONOLULU HI EP192015
500 AM HST SAT OCT 24 2015

…HURRICANE OLAF TRACKING NORTH…WELL EAST OF THE BIG ISLAND OF
HAWAII…

SUMMARY OF 500 AM HST…1500 UTC…INFORMATION
———————————————-
LOCATION…19.3N 145.3W
ABOUT 640 MI…1025 KM E OF HILO HAWAII
ABOUT 825 MI…1330 KM E OF HONOLULU HAWAII
MAXIMUM SUSTAINED WINDS…120 MPH…195 KM/H
PRESENT MOVEMENT…NNE OR 30 DEGREES AT 8 MPH…13 KM/H
MINIMUM CENTRAL PRESSURE…955 MB…28.20 INCHES

WATCHES AND WARNINGS
——————–
THERE ARE NO COASTAL WATCHES OR WARNINGS IN EFFECT.

DISCUSSION AND 48-HOUR OUTLOOK
——————————
AT 500 AM HST…1500 UTC…THE CENTER OF HURRICANE OLAF WAS LOCATED
NEAR LATITUDE 19.3 NORTH…LONGITUDE 145.3 WEST. OLAF IS MOVING
TOWARD THE NORTH-NORTHEAST NEAR 8 MPH…13 KM/H. THE TRACK IS
FORECAST TO CURVE SLIGHTLY TO THE NORTHEAST OVER THE NEXT 48 HOURS
WITH LITTLE CHANGE IN FORWARD SPEED.

MAXIMUM SUSTAINED WINDS ARE NEAR 120 MPH…195 KM/H…WITH HIGHER
GUSTS. OLAF IS A CATEGORY THREE HURRICANE ON THE SAFFIR-SIMPSON
HURRICANE WIND SCALE. GRADUAL WEAKENING IS EXPECTED THROUGH SUNDAY
NIGHT.

HURRICANE FORCE WINDS EXTEND OUTWARD UP TO 30 MILES…45 KM…FROM
THE CENTER…AND TROPICAL STORM FORCE WINDS EXTEND OUTWARD UP TO 175
MILES…280 KM.

THE ESTIMATED MINIMUM CENTRAL PRESSURE IS 955 MB…28.20 INCHES.

HAZARDS AFFECTING LAND
———————-
SURF…SWELLS GENERATED BY HURRICANE OLAF WILL PRODUCE
LIFE-THREATENING AND POTENTIALLY DAMAGING SURF ALONG EAST FACING
SHORES OF THE HAWAIIAN ISLANDS INTO THIS WEEKEND. SEE THE COASTAL
HAZARD MESSAGE ISSUED BY THE NATIONAL WEATHER SERVICE FORECAST
OFFICE IN HONOLULU FOR DETAILS.

NEXT ADVISORY
————-
NEXT COMPLETE ADVISORY…1100 AM HST.

$$
FORECASTER DONALDSON

WTPA45 PHFO 241443
TCDCP5

HURRICANE OLAF DISCUSSION NUMBER 39
NWS CENTRAL PACIFIC HURRICANE CENTER HONOLULU HI EP192015
500 AM HST SAT OCT 24 2015

THE DVORAK SUBJECTIVE ESTIMATES FROM JTWC AND SAB WERE 5.0/90 KT…
AND 5.5/102 KT FROM HFO. THE UW-CIMSS OBJECTIVE ESTIMATE WAS
6.0/115.0 KT. THE EYE HAS DISAPPEARED OVER THE PAST 6 HOURS…BUT
VERY COLD CLOUDS STILL COVER THE CENTER. THE INITIAL INTENSITY FOR
THIS ADVISORY WILL BE KEPT AT 105 KT.

THE INITIAL MOTION FOR THIS ADVISORY IS 030 DEGREES AT 7 KT WITH
FAIR CONFIDENCE IN RECENT CENTER POSITIONS. OLAF IS MOVING
THROUGH A WEAKNESS IN THE SUBTROPICAL RIDGE WHILE A SHORT-WAVE
TROUGH MOVES EASTWARD FAR NORTH OF THE HURRICANE. OLAF IS FORECAST
TO CURVE SLIGHTLY TOWARD THE NORTHEAST OVER THE NEXT COUPLE OF DAYS.
THE TRACK GUIDANCE REMAINS IN GOOD AGREEMENT FOR THE NEXT FEW DAYS.
THE CURRENT FORECAST REMAINS CLOSE TO THE GUIDANCE AND THE PREVIOUS
TRACK.

SHIPS SHOWS 31 KT OF VERTICAL WIND SHEAR…VWS…FROM THE
SOUTHWEST…WHILE UW-CIMSS SHOWS 36 KT FROM THE SOUTHWEST.
OLAF REMAINS 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 ABRUPT. THE MODEL GUIDANCE
HAS BECOME MORE CONSISTENT DEPICTING THE DIRECTIONAL CHANGE…BUT
THERE IS STILL QUITE A BIT OF SPREAD IN THE GUIDANCE. THIS FORECAST
HAS A SHARPER TURN TO THE WEST AND SHOWS OLAF MOVING FASTER AFTER
THE TURN.

FORECAST POSITIONS AND MAX WINDS

INIT 24/1500Z 19.3N 145.3W 105 KT 120 MPH
12H 25/0000Z 20.2N 144.7W 90 KT 105 MPH
24H 25/1200Z 21.3N 143.9W 80 KT 90 MPH
36H 26/0000Z 22.2N 143.2W 65 KT 75 MPH
48H 26/1200Z 23.4N 142.2W 55 KT 65 MPH
72H 27/1200Z 25.0N 140.0W 40 KT 45 MPH
96H 28/1200Z 26.0N 140.0W 35 KT 40 MPH
120H 29/1200Z 26.0N 144.0W 30 KT 35 MPH

$$
FORECASTER DONALDSON
H