WTNT42 KNHC 160256 RRA

TCDAT2



TROPICAL STORM KARL DISCUSSION NUMBER   7

NWS NATIONAL HURRICANE CENTER MIAMI FL       AL122016

1100 PM AST THU SEP 15 2016



DURING THE PAST SIX HOURS, A SIGNIFICANT INCREASE IN THE AMOUNT AND

THE ORGANIZATION OF THE DEEP CONVECTION HAS OCCURRED NEAR AND OVER

THE WELL-DEFINED LOW-LEVEL CIRCULATION CENTER. THE SOUTHWESTERN EDGE

OF THE COLD CLOUD CANOPY, CHARACTERIZED BY TOPS AS COLD AS -89C, HAS

CONTINUED TO EXPAND SOUTHWESTWARD OVER THE CENTER DESPITE

SOUTHWESTERLY VERTICAL WIND SHEAR OF 20-25 KT. THE INITIAL INTENSITY

HAS BEEN INCREASED TO 40 KT BASED ON A CONSTRAINED DVORAK SATELLITE

ESTIMATE OF 35 KT FORM TAFB, BUT WITH A DATA T-NUMBER OF T3.0/45 KT

USING A SHEAR PATTERN. A 15/2247Z PARTIAL ASCAT-B PASS INDICATED

SEVERAL 35-36 KT SURFACE WIND VECTORS IN THE NORTHEASTERN QUADRANT

MORE THAN 60 NMI FROM THE CENTER. BASED ON CONTINUED IMPROVEMENT IN

THE SATELLITE PRESENTATION SINCE THE ASCAT PASS, THE INITIAL

INTENSITY IS SET AT 40 KT, MAKING KARL THE ELEVENTH NAMED STORM OF

THE SEASON.



KARL IS MOVING WESTWARD OR 275/11 KT. THE CYCLONE IS EXPECTED TO

MOVE WESTWARD AND THEN WEST-SOUTHWESTWARD AROUND A STRENGTHENING

ATLANTIC SUBTROPICAL RIDGE FOR THE NEXT 48-72 HOURS. AFTER THAT

TIME, THE RIDGE IS FORECAST TO WEAKEN SOME, ALLOWING KARL TO TURN

BACK TOWARD THE WEST AND THEN WEST-NORTHWEST BY DAY 5. THE NEW NHC

FORECAST IS ESSENTIALLY ON TOP OF THE PREVIOUS ADVISORY TRACK, AND

LIES CLOSE TO THE MULTI-MODEL CONSENSUS TVCX AND THE FLORIDA STATE

SUPERENSEMBLE MODEL.



KARL IS EXPECTED TO REMAIN IN A MODERATE TO STRONG VERTICAL WIND

SHEAR ENVIRONMENT FOR THE NEXT 36 HOURS OR SO, WHICH SHOULD INHIBIT=