WTPZ44 KNHC 242034 RRA

TCDEP4



HURRICANE HILARY DISCUSSION NUMBER  14

NWS NATIONAL HURRICANE CENTER MIAMI FL       EP092017

400 PM CDT MON JUL 24 2017



HILARY CONTINUES TO DISPLAY A SMALL CENTRAL CORE WITH VERY DEEP

CONVECTIVE TOPS AND LOTS OF BANDING IN THE OUTER CIRCULATION.

ALTHOUGH AN EYE IS NOT APPARENT IN VISIBLE IMAGERY, WINDSAT

MICROWAVE DATA FROM EARLIER SHOW THAT THE HURRICANE HAS A DISTINCT

EYE UNDERNEATH THE CLOUD CANOPY.  SATELLITE ESTIMATES CONTINUE TO

INCREASE, SO THE INITIAL WIND SPEED IS SET TO 75 KT, CLOSE TO THE

LATEST SAB FIX.



THE HURRICANE HAS BEEN STRENGTHENING QUICKLY DURING THE PAST 24 H,

NEAR THE THRESHOLD OF RAPID INTENSIFICATION.  WITH NO SIGNIFICANT

CHANGES TO THE FAVORABLE OCEANIC AND ATMOSPHERIC ENVIRONMENTS

FORECAST, THERE IS GOOD REASON TO SHOW A SIMILAR RATE OF

STRENGTHENING FOR THE FIRST 24 HOURS OF THE FORECAST.  AFTER THAT

TIME, MODELS ARE INDICATING AN INCREASE IN NORTHERLY WIND SHEAR,

PARTIALLY ASSOCIATED WITH AN ENHANCED ANTICYCLONIC OUTFLOW FROM TS

IRWIN. THIS MIGHT LIMIT THE PEAK INTENSITY, SO THE WIND SPEED

FORECAST HAS BEEN LEVELED OFF ON DAY 2.  THE LATEST MODEL GUIDANCE

HAS COME IN CLOSER TO THE PREVIOUS OFFICIAL FORECAST, SO LITTLE

CHANGE HAS BEEN MADE IN THE NEW NHC INTENSITY PREDICTION.  SOME

WEAKENING IS LIKELY AT LONGER RANGE DUE TO COOLER SSTS, ENTRAINMENT

OF DRIER AIR, AND BINARY INTERACTION WITH IRWIN.



THE INITIAL MOTION ESTIMATE IS 300/7 KT.  A RIDGE THAT EXTENDS INTO

THE EASTERN PACIFIC FROM THE SOUTHWESTERN UNITED STATES IS FORECAST

TO STRENGTHEN SLIGHTLY OVER THE NEXT COUPLE OF DAYS, WHICH SHOULD

STEER HILARY A LITTLE TO THE LEFT AND A BIT FASTER DURING THAT TIME.