WTPZ42 KNHC 062048 RRA

TCDEP2



HURRICANE JOHN DISCUSSION NUMBER   5

NWS NATIONAL HURRICANE CENTER MIAMI FL       EP122018

300 PM MDT MON AUG 06 2018



JOHN HAS CONTINUED TO INTENSIFY SINCE THE PREVIOUS ADVISORY.

VISIBLE SATELLITE IMAGES CONTINUE TO INDICATE AN INCREASE IN

BANDING AND VERY RECENT PICTURES SHOW THE FORMATION OF A BANDING

EYE.  AS A RESULT, THE INITIAL INTENSITY IS INCREASED TO 65 KT,

WHICH IS BASED ON A TAFB DVORAK T-NUMBER OF 4.0 AND UW/CIMSS

OBJECTIVE DVORAK ESTIMATES THAT ARE CLOSE TO 65 KT.  JOHN BECOMES

THE FIFTH HURRICANE OF THE 2018 EASTERN NORTH PACIFIC HURRICANE

SEASON.



JOHN IS FORECAST TO REMAIN WITHIN A VERY FAVORABLE ENVIRONMENT FOR

STRENGTHENING DURING THE NEXT DAY OR SO.  ALTHOUGH SOME OF THE

INTENSITY GUIDANCE IS NOT QUITE AS AGGRESSIVE AS THIS MORNING, THE

VARIOUS RAPID INTENSIFICATION INDICES STILL SHOW A HIGH LIKELIHOOD

OF RAPID STRENGTHENING DURING THE NEXT 24 HOURS.  THE NHC FORECAST

ONCE AGAIN CALLS FOR RAPID INTENSIFICATION AND BRINGS JOHN TO MAJOR

HURRICANE STRENGTH WITHIN 36 H. THE UPDATED NHC INTENSITY FORECAST

IS NEAR THE UPPER-END OF THE GUIDANCE IN BEST AGREEMENT WITH THE

LATEST SHIPS, HCCA, AND FSSE MODELS.  AFTER 48 H, JOHN WILL BE

MOVING OVER MUCH COOLER WATERS AND INTO A LESS CONDUCIVE

THERMODYNAMIC ENVIRONMENT.  THIS SHOULD RESULT IN RAPID WEAKENING,

AND JOHN IS FORECAST TO BECOME A REMNANT LOW BY DAY 5.



JOHN IS MOVING NORTHWESTWARD AT ABOUT 7 KT.  THE HURRICANE IS

FORECAST TO MOVE NORTHWESTWARD AROUND THE WESTERN PERIPHERY OF A

MID-LEVEL RIDGE OVER NORTHERN MEXICO DURING THE NEXT FEW DAYS.  ONCE

THE SYSTEM WEAKENS AND BECOMES A MORE SHALLOW CYCLONE LATE IN THE