WTPZ41 KNHC 190240 RRA

TCDEP1



TROPICAL STORM ESTELLE DISCUSSION NUMBER  15

NWS NATIONAL HURRICANE CENTER MIAMI FL       EP062016

800 PM PDT MON JUL 18 2016



THE SATELLITE PRESENTATION OF ESTELLE HAS DEGRADED A BIT IN THE

PAST FEW HOURS WITH SOME WARMING CLOUD-TOP TEMPERATURES NOTED NEAR

THE CENTER.  CONVECTIVE TOWERS HAVE BEEN SEEMINGLY JUST ROTATING

AROUND THE CENTER WITHOUT ANY APPRECIABLE INCREASE IN INNER-CORE

STRUCTURE.  SATELLITE CLASSIFICATIONS HAVE DROPPED A BIT, SO THE

INITIAL WIND SPEED WILL BE LOWERED TO 55 KT FOR THIS ADVISORY.



IT IS A LITTLE PUZZLING WHY ESTELLE HAS NOT INTENSIFIED BUT IT IS

LIKELY RELATED TO THE CYCLONE'S LARGE SIZE AND RADIUS OF MAXIMUM

WIND, ALONG WITH ANY LINGERING DRY MID-LEVEL AIR.  WITH ESTELLE

REMAINING OVER WARM WATER AND EXPERIENCING LIGHT SHEAR FOR THE NEXT

DAY OR SO, IT MAKES SENSE TO THINK THE EARLIER NEGATIVE CONDITIONS

WOULD EVENTUALLY BE OVERCOME.  THERE IS A SPLIT TONIGHT IN THE

GUIDANCE, HOWEVER, WITH THE STATISTICAL-DYNAMICAL AIDS

(SHIPS/LGEM) BASICALLY SHOWING NO INTENSIFICATION, WHILE THE

REGIONAL DYNAMICAL MODELS (HWRF/GFDL) ARE FORECASTING ESTELLE TO

BECOME A HURRICANE.  GIVEN WHAT HAS OCCURRED SO FAR, IT IS PRUDENT

TO DROP THE INTENSITY FORECAST FROM THE PREVIOUS ONE, BUT NOT YET

GIVE UP ON ESTELLE BECOMING A HURRICANE.  A MORE CONSISTENT

WEAKENING SHOULD BEGIN IN A COUPLE OF DAYS OVER COOL WATERS, WITH

REMNANT LOW STATUS LIKELY BY DAY 4.



MICROWAVE AND SATELLITE DATA INDICATE THAT ESTELLE CONTINUES TO

MOVE WEST-NORTHWESTWARD.  A LARGE RIDGE OVER THE EASTERN PACIFIC HAS

BEEN PROVIDING A STEADY STEERING CURRENT FOR THE CYCLONE.  ESTELLE

SHOULD CONTINUE MOVING WESTWARD TO WEST-NORTHWESTWARD FOR THE NEXT=