WTNT42 KNHC 192043 RRA

TCDAT2



TROPICAL STORM KARL DISCUSSION NUMBER  22

NWS NATIONAL HURRICANE CENTER MIAMI FL       AL122016

ISSUED BY THE NWS WEATHER PREDICTION CENTER COLLEGE PARK MD

500 PM AST MON SEP 19 2016



DEEP CONVECTION ASSOCIATED WITH KARL HAS INCREASED DURING THE DAY,

AND THE LOW-LEVEL CENTER IS NOW EMBEDDED BENEATH THE CONVECTIVE

CANOPY.  DVORAK INTENSITY ESTIMATES FROM TAFB AND SAB INCREASED TO

T2.5/35 KT AND T2.0/30 KT, RESPECTIVELY, BUT THESE NUMBERS DO NOT

YET SUPPORT AN INCREASE IN THE INITIAL INTENSITY OF 35 KT THAT HAS

BEEN CARRIED IN THE PREVIOUS FEW ADVISORIES.  SHIPS AND UW-CIMSS

SHEAR ANALYSES INDICATE THAT THE SOUTHWESTERLY SHEAR OVER KARL

REMAINS 10-15 KT.  HOWEVER, THE GUIDANCE SHOWS THE SHEAR DECREASING,

AND THE IMPROVING STRUCTURE OF KARL SUGGESTS THAT THIS MAY BE

ALREADY OCCURRING.  IN ADDITION, MOISTURE IN THE MIDDLE LEVELS OF

THE ATMOSPHERE IS EXPECTED TO GRADUALLY INCREASE, AND SSTS WILL BE

BETWEEN 28-30C FOR THE NEXT FIVE DAYS.  ALL THESE INGREDIENTS

SUGGEST THAT STRENGTHENING IS LIKELY, AND THE OFFICIAL FORECAST

CONTINUES TO SHOW INTENSIFICATION STARTING SLOWLY AT FIRST AND THEN

BECOMING FASTER AFTER 48 HOURS.  THIS FORECAST IS VERY CLOSE TO A

CONSENSUS OF THE SHIPS AND LGEM MODELS, AND THE NEW OFFICIAL

FORECAST IS ESSENTIALLY AN UPDATE OF THE PREVIOUS FORECAST.



THE CENTER OF KARL JOGGED NORTHWESTWARD DURING THE DAY, AND THE

LONG-TERM MOTION ESTIMATE IS NOW WEST-NORTHWESTWARD, OR 290/10 KT.

A WEST-NORTHWESTWARD MOTION IS EXPECTED TO CONTINUE FOR THE NEXT

COUPLE OF DAYS WHILE KARL MOVES ALONG THE SOUTHERN EDGE OF THE

SUBTROPICAL RIDGE.  AFTER THAT TIME, KARL IS FORECAST TO REACH THE=