WTPZ44 KNHC 290845 RRA

TCDEP4



TROPICAL STORM HILARY DISCUSSION NUMBER  32

NWS NATIONAL HURRICANE CENTER MIAMI FL       EP092017

200 AM PDT SAT JUL 29 2017



THE DEEP CONVECTION ASSOCIATED WITH HILARY HAS LOST SOME

ORGANIZATION SINCE THE LAST ADVISORY, WITH LITTLE OR NO CONVECTION

CURRENTLY OCCURRING OVER THE WESTERN SEMICIRCLE. SATELLITE

INTENSITY ESTIMATES RANGE FROM 45-65 KT, AND RECENT ASCAT DATA

SHOWED WINDS OF AT BEST 50 KT.  BASED ON THESE, THE INITIAL

INTENSITY IS NUDGED DOWN TO A POSSIBLY GENEROUS 55 KT.  THE SYSTEM

WILL BE MOVING OVER PROGRESSIVELY COOLER WATER AND INTO A MORE

STABLE ENVIRONMENT, WHICH SHOULD CAUSE A STEADY WEAKENING.  BY 48

HOURS, HILARY IS FORECAST TO BECOME A REMNANT LOW OVER 23C WATERS,

AND THE CYCLONE IS FORECAST TO DISSIPATE COMPLETELY AFTER 96 HR.



THE INITIAL MOTION IS NOW 305/9.  AS MENTIONED IN THE PREVIOUS

ADVISORY, A MID-LEVEL RIDGE EXTENDING FROM SOUTHERN CALIFORNIA

WEST-SOUTHWESTWARD ACROSS THE EASTERN PACIFIC SHOULD STEER HILARY

ON THIS GENERAL PATH FOR THE NEXT COUPLE OF DAYS.  THE FORECAST THEN

GETS MORE COMPLICATED DUE TO POTENTIAL INTERACTION WITH TS IRWIN.

THE GUIDANCE IS IN LESS GOOD AGREEMENT THAN EARLIER, WITH THE

POSSIBILITIES RANGING FROM THE CANADIAN MODEL MERGING THE TWO

SYSTEMS IN 72 H TO THE ECMWF SHOWING THEM DISSIPATING IN CLOSE

PROXIMITY TO ONE ANOTHER NEAR 120 H.  THE TRACK GUIDANCE SUGGESTS A

WEST-NORTHWESTWARD TO WESTWARD TURN FOR HILARY AS IRWIN OR ITS

REMNANTS MOVE AROUND THE EASTERN AND NORTHERN SIDES, AND THE

OFFICIAL FORECAST FOLLOWS THIS SCENARIO.  THE NEW FORECAST TRACK IS

SIMILAR TO THE PREVIOUS TRACK FOR THE FIRST 36-48 H AND THEN IS