WTPA42 PHFO 050241

TCDCP2



TROPICAL STORM OHO DISCUSSION NUMBER   8

NWS CENTRAL PACIFIC HURRICANE CENTER HONOLULU HI   CP072015

500 PM HST SUN OCT 04 2015



VISIBLE ANIMATION SHOWS THE LOW LEVEL CIRCULATION CENTER...

LLCC...REMAINS EXPOSED BENEATH THIN CIRRUS JUST NORTHEAST OF DEEP

CONVECTION. FIX CONFIDENCE IS QUITE HIGH AS OVERALL SATELLITE

PRESENTATION HAS CHANGED LITTLE SINCE LATE THIS MORNING. SUBJECTIVE

DVORAK SATELLITE INTENSITY ESTIMATES ARE ALL 2.0...30 KT...FROM THE

THREE SATELLITE CENTERS...WHILE UW-CIMSS ADT REMAINS 2.7...39 KT.

HOWEVER...A SONDE DROPPED BY THE G-IV AIRCRAFT...CURRENTLY FLYING A

TRUNCATED HIGH-ALTITUDE MISSION AROUND THE PERIPHERY OF OHO...SHOWED

A SPLASH WIND OF 195/39 KT ABOUT 40 NM EAST SOUTHEAST OF THE LLCC.

SPLASH PRESSURE WAS 999 MB. THIS DATA TRUMPS DVORAK ESTIMATES AND WE

WILL INCREASE THE INITIAL INTENSITY OF OHO TO 40 KT WITH THIS

ADVISORY. THIS DATA WAS ALSO USED TO INCREASE THE GALE RADII FOR

THIS SYSTEM.



OHO APPEARS TO BE MOVING NORTHEASTWARD NOW...WITH AN INITIAL MOTION

OF 045/04 KT. OHO IS SEEING ABOUT 15 KT OF EASTERLY SHEAR...WHICH

EXPLAINS THE DISPLACEMENT OF ASSOCIATED DEEP CONVECTION TO THE WEST

OF THE LLCC AND THE WESTWARD TILT OF THE ROTATING CORE WITH HEIGHT.

STEERING INFLUENCES REMAIN WEAK AND INCLUDE A MID-LEVEL RIDGE WHICH

EXTENDS WESTWARD FROM THE EASTERN PACIFIC AND A DEEP TROUGH

DEVELOPING NORTHWEST OF THE HAWAIIAN ISLANDS. HOWEVER...THE LATTER

IS BEGINNING TO WIN OUT GIVEN WHAT APPEARS TO BE SUSTAINED NORTHEAST

MOVEMENT. TRACK GUIDANCE CONTINUES TO BE TIGHTLY PACKED...WITH

SUSTAINED NORTHEAST MOTION INDICATED THROUGH THE NEXT FIVE DAYS.

CONSENSUS HAS SHIFTED A BIT TO THE RIGHT AT MEDIUM AND LONG

RANGES. THE FORWARD MOTION SPREAD HAS DECREASED...WITH MORE AND

MORE GUIDANCE MOVING OHO DOWN ITS TRACK FASTER BEYOND 24 HOURS. THE

CURRENT FORECAST TRACK HAS BEEN SHIFTED TO THE RIGHT A BIT...FOR

INITIAL MOTION THROUGH 24 HOURS...THEN TO MATCH UP WITH THE

CONSENSUS TRACKS AFTERWARDS. THE FORECAST TRACK IS NOW A BIT LONGER

AS WELL...WITH FORWARD MOTION NUDGED HIGHER AT MEDIUM AND LONG

RANGES.



MOST INTENSITY GUIDANCE CONTINUE TO INDICATE THAT OHO WILL REMAIN A

TROPICAL STORM THROUGH THE FORECAST PERIOD...IN SPITE OF MOVING

ACROSS 28C TO 29C WATER THROUGH 48 HOURS. SHEAR IS EXPECTED TO

INCREASE ACROSS OHO BEYOND 48 HOURS AS THE DEEP TROUGH NORTH OF

HAWAII DIGS SOUTHEASTWARD AND BEGINS TO SCOOP THIS SYSTEM OUT OF THE

DEEP TROPICS ACROSS COOLER WATER. HOWEVER...SOME STRENGTHENING IS

EXPECTED UNTIL THEN AS SHEAR REMAINS MODERATE TODAY...THEN ACTUALLY

DECREASES SLIGHTLY ON MONDAY. AFTER ADJUSTING FOR THE INITIAL

INTENSITY INCREASE...THE INTENSITY TREND FOR THIS ADVISORY CLOSELY

FOLLOWS THE PREVIOUS ONE...CAPPING INTENSITY AT 55 KT AT 48 AND 72

HOURS...WITH GRADUAL WEAKENING AFTERWARDS. THIS IS IN LINE WITH

SHIPS BUT BELOW HWRF AND GFDL.



THE 53RD WEATHER RECONNAISSANCE SQUADRON HAS BEEN TASKED TO FLY THIS

SYSTEM IN SUPPORT OF CPHC OPERATIONS. INITIAL FLIGHTS INTO THE

SYSTEM ARE PLANNED FOR THIS EVENING AND MONDAY MORNING.

ADDITIONALLY...THE G-IV AIRCRAFT WILL FLY SYNOPTIC MISSIONS...WITH

ANOTHER HIGH-ALTITUDE FLIGHT PLANNED MONDAY MORNING...IN ORDER FOR

THE DATA TO BE UTILIZED BY AFTERNOON MODEL RUNS.





FORECAST POSITIONS AND MAX WINDS



INIT  05/0300Z 13.8N 154.7W   40 KT  45 MPH

 12H  05/1200Z 14.2N 154.4W   45 KT  50 MPH

 24H  06/0000Z 14.9N 153.8W   50 KT  60 MPH

 36H  06/1200Z 15.7N 152.9W   50 KT  60 MPH

 48H  07/0000Z 16.6N 151.9W   55 KT  65 MPH

 72H  08/0000Z 19.7N 149.0W   55 KT  65 MPH

 96H  09/0000Z 24.4N 146.3W   50 KT  60 MPH

120H  10/0000Z 30.1N 141.8W   45 KT  50 MPH



$$

FORECASTER POWELL