WTPZ45 KNHC 051436 RRA

TCDEP5



HURRICANE HECTOR DISCUSSION NUMBER  20

NWS NATIONAL HURRICANE CENTER MIAMI FL       EP102018

800 AM PDT SUN AUG 05 2018



HECTOR CONTINUES TO MAINTAIN A 10-15 N MI WIDE EYE SURROUNDED BY A

RING OF -60 TO -70 DEGREES CELSIUS CLOUD TOPS.  THE EYE HAS BECOME

SLIGHTLY LESS DISTINCT THIS MORNING AND RECENT MICROWAVE DATA

SUGGEST THAT AN EYEWALL REPLACEMENT CYCLE COULD BE OCCURRING.  A

1111 UTC AMSR2 MICROWAVE OVERPASS SHOWS A DOUBLE EYEWALL STRUCTURE

WITH THE INNER EYEWALL OPEN TO THE SOUTHWEST.  THE VARIOUS

SUBJECTIVE AND OBJECTIVE SATELLITE ESTIMATES ARE BETWEEN 102-110

KT, AND THE INITIAL WIND SPEED IS KEPT NEAR THE UPPER-END OF THESE

ESTIMATES FOR NOW.



THE HURRICANE IS MOVING WESTWARD OR 275/10 KT.  A WESTWARD TO

WEST-NORTHWESTWARD MOTION IS EXPECTED OVER THE NEXT DAY OR SO AS

HECTOR IS STEERED BY A DEEP-LAYER RIDGE TO ITS NORTH.  THE RIDGE IS

FORECAST TO STRENGTHEN NORTH OF THE HAWAIIAN ISLANDS BY MID-WEEK

WHICH SHOULD CAUSE THE HURRICANE TO MOVE ON A GENERAL WESTWARD

TRACK THROUGHOUT MOST OF THE REMAINDER OF THE FORECAST PERIOD.

WHILE ALL OF THE DYNAMICAL MODELS ARE IN AGREEMENT ON THE OVERALL

SCENARIO THERE IS A FAIRLY TYPICAL AMOUNT OF CROSS-TRACK SPREAD WITH

THE ECMWF ALONG THE SOUTHERN EDGE OF THE GUIDANCE ENVELOPE AND THE

HMON AND GFS ALONG THE NORTHERN SIDE.  THE UPDATED NHC TRACK

FORECAST IS CLOSE TO THE LATEST CONSENSUS AIDS, AND LITTLE OVERALL

CHANGE TO THE PREVIOUS FORECAST WAS REQUIRED.



HECTOR IS FORECAST TO REMAIN OVER WARM SSTS AND WITHIN A LOW SHEAR

ENVIRONMENT FOR THE NEXT COUPLE OF DAYS, AND IT IS POSSIBLE FOR SOME

FLUCTUATIONS IN INTENSITY TO OCCUR AS THE RESULT OF EYEWALL