WTPZ42 KNHC 022039 RRA

TCDEP2



TROPICAL STORM OLIVIA DISCUSSION NUMBER   8

NWS NATIONAL HURRICANE CENTER MIAMI FL       EP172018

300 PM MDT SUN SEP 02 2018



OLIVIA REMAINS A SHEARED TROPICAL CYCLONE WITH THE LOW-LEVEL CENTER

LOCATED TO THE NORTH AND NORTHEAST OF THE LARGE AREA OF DEEP

CONVECTION.  RECENT ASCAT DATA REVEALED A LARGE AREA OF 35-40 KT

WINDS OVER THE SOUTHEASTERN PORTION OF OLIVIA'S CIRCULATION, AND IS

THE BASIS FOR THE INITIAL WIND SPEED OF 40 KT.  THE GLOBAL MODELS

SUGGEST THAT THE NORTHEASTERLY SHEAR OVER THE CYCLONE WILL NOT

ABATE AS QUICKLY AS PREVIOUS INDICATED, AND MUCH OF THE INTENSITY

GUIDANCE SHOWS LESS STRENGTHENING THAN BEFORE.  THE NHC WIND SPEED

FORECAST HAS BEEN LOWERED TO BE CLOSE TO THE INTENSITY CONSENSUS,

BUT IT IS NOT AS LOW AS THE STATISTICAL GUIDANCE IN ORDER TO

MAINTAIN CONSISTENCY WITH THE PREVIOUS OFFICIAL FORECAST. OLIVIA IS

FOREAST TO REACH COOLER WATERS AROUND DAY 4 AND THE TROPICAL

CYCLONE SHOULD WEAKEN BY THAT TIME.



THE TROPICAL STORM IS MOVING WEST-NORTHWESTWARD OR 300/6 KT.

OLIVIA SHOULD TURN WESTWARD AS A LARGE RIDGE BUILDS TO THE NORTH OF

THE SYSTEM WITHIN THE NEXT COUPLE OF DAYS. AFTER MIDWEEK, OLIVIA

SHOULD TURN BACK TOWARD THE WEST-NORTHWEST AS IT REACHES THE

WESTERN PORTION OF THE RIDGE.  THE DYNAMICAL MODEL GUIDANCE

GENERALLY AGREES WITH THIS OVERALL SCENARIO, BUT THERE IS

CROSS-TRACK SPREAD REGARDING HOW MUCH LATITUDE THE SYSTEM

GAINS OVER THE NEXT COUPLE OF DAYS.  THE NHC TRACK IS NEAR THE

VARIOUS CONSENSUS AIDS AND THE GFS ENSEMBLE MEAN, BUT IT IS NOT AS

FAR NORTH AS THE LATEST RUN OF THE ECMWF THAT TAKES OLIVIA

MORE NORTHWESTWARD DURING THE NEXT 12 TO 24 HOURS.