WTPA42 PHFO 210303 RRA

TCDCP2



HURRICANE LANE DISCUSSION NUMBER  25

NWS CENTRAL PACIFIC HURRICANE CENTER HONOLULU HI   EP142018

500 PM HST MON AUG 20 2018



VISIBLE SATELLITE IMAGERY THIS AFTERNOON SHOWS AN IMPRESSIVE,

DISTINCT EYE ON HURRICANE LANE, THOUGH THE CONVECTION SURROUNDING

THE CORE LOOKS MORE RAGGED ON THE LAST FEW INFRARED IMAGES. A 2258Z

AMSR2 PASS INDICATED THAT LANE HAD A CONCENTRIC EYEWALL STRUCTURE.

SATELLITE INTENSITY ESTIMATES RANGED FROM 5.5 FROM SAB AND JTWC TO

6.0 FROM PHFO. CIMSS ADT HAD 5.5 AT 0000Z BUT HAS SINCE RISEN TO

6.0. BASED ON THESE ESTIMATES AND THE EARLIER RECONNAISANCE DATA,

WE HAVE MAINTAINED A 115 KT INTENSITY FOR THIS ADVISORY. ANOTHER

AIRCRAFT RECONNAISANCE MISSION WILL INVESTIGATE LANE THIS EVENING.



THE INITIAL MOTION ESTIMATE CONTINUES TO BE 280/10. A SUBTROPICAL

RIDGE TO THE NORTH OF LANE CONTINUES TO STEER THE SYSTEM WESTWARD.

HOWEVER, CHANGES IN THE STEERING PATTERN ARE EXPECTED RELATIVELY

SOON, AS THE RIDGE WEAKENS ANE LEAVES A WEAKNESS TO THE NORTH OF

LANE. THIS WILL ALLOW THE TROPICAL CYCLONE TO BEGIN GAINING

LATITUDE A LITTLE MORE QUICKLY BY 48 HOURS.



THE MODELS ARE STRUGGLING WITH A COUPLE OF FACTORS THAT MAKE THE

TRACK FORECAST BEYOND 48 HOURS VERY CHALLENGING. ONE IS THE

EVOLUTION OF A NEW RIDGE WHICH DEVELOPS TO THE EAST AND SOUTHEAST OF

LANE, AND THE OTHER IS THE EFFECT OF GRADUALLY INCREASING SHEAR. THE

ECMWF IS STRONGER WITH THE RIDGE, AND STARTS SHEARING THE SYSTEM

SOONER, SO THE TRACK IS ON THE LEFT SIDE OF THE GUIDANCE ENVELOPE.

THE GFS AND NAVGEM ARE QUITE A BIT WEAKER WITH THE RIDGE, AND KEEP

LANE AWAY FROM THE WESTERLY SHEAR LONGER. THERE DO NOT APPEAR TO BE