WTPA42 PHFO 071501

TCDCP2



HURRICANE OHO DISCUSSION NUMBER  18

NWS CENTRAL PACIFIC HURRICANE CENTER HONOLULU HI   CP072015

500 AM HST WED OCT 07 2015



OHO CONTINUES TO HAVE AN EYE IN INFRARED SATELLITE IMAGERY EARLY

THIS MORNING. HOWEVER...IT LIKELY REACHED THE PEAK OF THE

INTENSIFICATION PROCESS A FEW HOURS AGO...SINCE THE COLD CLOUD

TOPS SURROUNDING THE EYE ARE WARMING AND THE CLOUD STRUCTURE HAS

DEVELOPED AN ELONGATED NORTH TO SOUTH ORIENTED ELLIPTICAL SHAPE.

THIS DEGRADATION OF THE STRUCTURE OF THE INNER CORE IS PROBABLY DUE

TO INCREASINGLY HOSTILE SOUTHWESTERLY ENVIRONMENTAL VERTICAL WIND

SHEAR IN THE VICINITY OF OHO...WHICH IS ESTIMATED TO BE ABOUT 19 KT

ACCORDING TO SHIPS AND MORE THAN 40 KT BASED ON THE UW-CIMSS

GUIDANCE. THE LATEST SUBJECTIVE DVORAK SATELLITE INTENSITY ESTIMATES

FROM PHFO AND JTWC ARE 5.0/90 KT...WHILE SAB IS 5.5/102 KT. AT THE

SAME TIME...THE UW-CIMSS ESTIMATE IS 5.4/100 KT. AS A COMPROMISE

BETWEEN THESE VARIOUS ESTIMATES...WE ARE INCREASING THE INITIAL

INTENSITY TO 95 KT.



THE INITIAL MOTION IS 025/30 KT...WHICH IS THE RESULT OF STEERING

BY A DEEP NORTH TO SOUTH ORIENTED TROUGH LOCATED WEST-NORTHWEST OF

THE HURRICANE. THE STRONG SOUTHWESTERLY STEERING FLOW ASSOCIATED

WITH THIS DEEP TROUGH IS EXPECTED TO CONTINUE TRANSPORTING OHO

RAPIDLY TOWARD THE NORTH-NORTHEAST WITH STEADILY INCREASING FORWARD

SPEED. DESPITE THIS RAPID MOTION...THE FORECAST MODELS CONTINUE TO

BE IN VERY CLOSE AGREEMENT DURING THE NEXT 36 HOURS...WITH

INCREASING SPREAD BY DAY 2. THE LATEST FORECAST TRACK HAS BEEN

ADJUSTED SLIGHTLY TO THE WEST AND ACCELERATED COMPARED WITH THE

PREVIOUS FORECAST. THESE ALONG TRACK AND CROSS TRACK ADJUSTMENTS

WERE NUDGED TOWARD THE ECMWF MODEL OUTPUT...AS WELL AS THE LATEST

TVCN AND GFEX CONSENSUS GUIDANCE.



OHO IS CURRENTLY OVER SEA SURFACE TEMPERATURES /SST/ OF AROUND 26C.

THE LATEST FORECAST TRACK TAKES THE HURRICANE ACROSS DECREASING

VALUES OF SST AND REDUCED OCEAN HEAT CONTENT /OHC/ ACCORDING TO THE

MOST RECENT GUIDANCE FROM CIRA DURING THE NEXT 12 TO 18 HOURS. THE

SST AND OHC DECREASE DRAMATICALLY AFTER THAT. AT THE SAME TIME...

SHEAR IMPARTED BY THE DEEP TROUGH WILL LIKELY CONTINUE TO RAMP UP IN

THE VICINITY OF THE SYSTEM. AS A RESULT...OHO IS FORECAST TO

GRADUALLY WEAKEN DURING THE NEXT 24 HOURS. MORE RAPID WEAKENING IS

ANTICIPATED BEYOND 24 HOURS...WITH OHO EXPECTED TO NO LONGER HAVE

TROPICAL CHARACTERISTICS BY 36 HOURS DUE TO THE LOSS OF DEEP

CONVECTION NEAR THE INNER CORE. HOWEVER...BEYOND THAT TIME...THE

GLOBAL FORECAST MODELS SUCH AS THE GFS AND ECMWF CONTINUE TO SHOW

OHO WILL COMPLETE EXTRATROPICAL TRANSITION BY DAY 2. THIS LATEST

INTENSITY FORECAST CLOSELY FOLLOWS THE IVCN CONSENSUS AND SHIPS.



NOTE THAT THE CURRENT FORECAST TRACK HAS THE CENTER OF OHO

POTENTIALLY CROSSING LONGITUDE 140W INTO THE AREA OF RESPONSIBILITY

OF THE NATIONAL HURRICANE CENTER IN MIAMI FLORIDA BETWEEN 24 AND 36

HOURS FROM NOW. THERE IS QUITE A BIT OF UNCERTAINTY ABOUT WHETHER OR

NOT OHO WILL BE A VIABLE TROPICAL SYSTEM WHEN...AND IF...THIS

OCCURS. HOWEVER...SHOULD OHO ACTUALLY CROSS INTO THE NORTHEASTERN

PACIFIC BASIN AS A TROPICAL CYCLONE...THIS WILL BE A RARE

OCCURRENCE...AT LEAST IN THE SATELLITE ERA.





FORECAST POSITIONS AND MAX WINDS



INIT  07/1500Z 23.5N 145.9W   95 KT 110 MPH

 12H  08/0000Z 28.1N 144.6W   85 KT 100 MPH

 24H  08/1200Z 34.6N 141.5W   70 KT  80 MPH

 36H  09/0000Z 42.0N 137.0W   50 KT  60 MPH...POST-TROPICAL

 48H  09/1200Z 51.0N 133.0W   45 KT  50 MPH...POST-TROP/EXTRATROP

 72H  10/1200Z...DISSIPATED



$$

FORECASTER HOUSTON