WTPZ42 KNHC 211442 RRA

TCDEP2



TROPICAL STORM KAY DISCUSSION NUMBER  12

NWS NATIONAL HURRICANE CENTER MIAMI FL       EP122016

900 AM MDT SUN AUG 21 2016



KAY IS HOLDING ITS OWN.  A NEW BURST OF VERY COLD-TOPPED CONVECTION

HAS DEVELOPED SINCE THE LAST ADVISORY, COINCIDING WITH THE DIURNAL

CONVECTIVE MAXIMUM.  AN EARLIER MICROWAVE PASS SUGGESTED SOME TILT

BETWEEN THE LOW- AND MID-LEVEL CENTERS, INDICATIVE THAT

SOUTHEASTERLY SHEAR DIAGNOSED OVER THE STORM COULD BE SLIGHTLY

STRONGER THAN INDICATED IN ANALYSES. SATELLITE CLASSIFICATIONS ARE

T2.5/35 KT AND T3.0/45 KT FROM SAB AND TAFB, RESPECTIVELY, AND ADT

VALUES ARE AROUND T3.0.  A BLEND OF THESE DATA IS USED TO SET THE

INITIAL INTENSITY ESTIMATE TO 40 KT.



KAY IS LIVING ON BORROWED TIME.  WITHIN 24 HOURS, THE CYCLONE

SHOULD CROSS THE 26-DEG C ISOTHERM AND ENCOUNTER A DRIER AND MORE

STABLE AIR MASS.  WEAKENING SHOULD HAVE BEGUN BY THEN IF NOT

BEFORE, AND A RAPID DECAY IS EXPECTED IN 24 TO 48 HOURS WHEN KAY

MOVES ROUGHLY PERPENDICULAR TO A STEEP GRADIENT OF LOWER SSTS AND IS

AFFECTED BY INCREASINGLY UNFAVORABLE THERMODYNAMICS CONDITIONS.

REMNANT LOW STATUS IS INDICATED IN 48 HOURS, AND THE SYSTEM SHOULD

DISSIPATE JUST AFTER 72 HOURS PER THE GLOBAL MODELS. THE NEW NHC

INTENSITY FORECAST MAINTAINS THE CYCLONE'S CURRENT INTENSITY FOR

THE NEXT 12 HOURS, BUT OVERALL IS SIMILAR TO THE PREVIOUS ONE AND

THE BULK OF THE INTENSITY GUIDANCE AFTER THAT TIME.



KAY IS MOVING WEST-NORTHWESTWARD TO NORTHWESTWARD, WITH AN INITIAL

MOTION ESTIMATE OF 305/06.  FOR THE NEXT DAY OR SO, THIS GENERAL

MOTION SHOULD CONTINUE WHILE THE CYCLONE IS STEERED BY THE WEAK FLOW

AROUND THE WESTERN PERIPHERY OF A MID-LEVEL RIDGE OVER NORTHERN=