WTPA41 PHFO 052054 RRA

TCDCP1



TROPICAL STORM WALAKA DISCUSSION NUMBER  25

NWS CENTRAL PACIFIC HURRICANE CENTER HONOLULU HI   CP012018

1100 AM HST FRI OCT 05 2018



WALAKA, WHICH HAS BEEN DETERIORATING STEADILY ALL NIGHT, IS NOW

COMING APART AT THE SEAMS IN SATELLITE IMAGERY. THE EXPOSED LOW

LEVEL CIRCULATION CENTER (LLCC) IS BEGINNING TO OPEN UP TO THE

WEST, WITH LAYERED CLOUDS AND POSSIBLY A SINGLE WARM-TOPPED

CUMULONIMBUS SPUTTERING WITHIN THE EASTERN QUADRANT. THE LATEST

DVORAK CURRENT INTENSITY ESTIMATES RANGE FROM 1.5/25 KT FROM JTWC TO

3.0/45 KT FROM PHFO. SAB ESTIMATED 2.0/30 KT WHILE UW-CIMSS ADT WAS

39 KT. BASED ON THESE ESTIMATES, AND WITH A NOD TO CONTINUITY, WE

WILL ASSIGN AN INITIAL INTENSITY OF 45 KT FOR THIS ADVISORY.

HOWEVER, THIS MAY BE GENEROUS GIVEN THE POOR SATELLITE PRESENTATION

AND THE DVORAK CONSTRAINTS KEEPING THE PHFO ESTIMATE HIGH.



THIS WEAKENING SYSTEM IS TRACKING JUST EAST OF DUE NORTH, WITH

INITIAL MOTION OF 030/10 KT. AFTER MOVING NORTHWARD OVER THE PAST

FEW DAYS ALONG THE WESTERN FRINGE OF THE SUBTROPICAL RIDGE, WALAKA

IS BEGINNING TO RESPOND TO SOUTHWESTERLY STEERING AHEAD OF A BROAD

NORTH PACIFIC UPPER TROUGH MOVING IN FROM THE NORTHWEST. THIS WILL

PICK WALAKA UP AND ACCELERATE IT OFF TO THE NORTHEAST THROUGH EARLY

SUNDAY. WALAKA IS EXPECTED TO BEGIN EXTRA-TROPICAL TRANSITION

SATURDAY. THE OFFICIAL FORECAST TRACK IS VERY CLOSE TO THAT OF THE

PREVIOUS ADVISORY, STAYING WITHIN THE VERY TIGHT GUIDANCE ENVELOPE

CENTERED ALONG HWRF. THE TRACK TERMINATES AT 48 HOURS AS WALAKA

BECOMES ABSORBED BY A MID-LATITUDE LOW.



WALAKA WILL MOVE OVER INCREASINGLY COOLER WATER ALONG ITS TRUNCATED