MESOSCALE DISCUSSION 2121
   NWS STORM PREDICTION CENTER NORMAN OK
   1050 PM CDT THU OCT 18 2007
   
   AREAS AFFECTED...CNTRL KY...WCNTRL/SWRN OH
   
   CONCERNING...TORNADO WATCH 725...
   
   VALID 190350Z - 190515Z
   
   THE SEVERE WEATHER THREAT FOR TORNADO WATCH 725 CONTINUES.
   
   VWP TIME SERIES FROM ILN/LVX SUGGEST THAT THE WINDS IN ROUGHLY THE
   3-6 KM LAYER HAVE BEEN BACKING SINCE 01Z...INDICATIVE OF THE UPR
   TROUGH BECOMING MORE NEGATIVELY TILTED OVER THE GRTLKS REGION.  THIS
   HAS PROBABLY CONTRIBUTED TO STORM MODE BECOMING INCREASINGLY LINEAR
   JUST SE OF THE OH RVR VLY FROM NCNTRL KY SWWD INTO THE TN VLY AT
   LATE EVENING.  AT THE SAME TIME...HOWEVER...BULK SHEAR WAS AOA 60
   KTS AND WILL CONTINUE TO SUPPORT EMBEDDED SUPERCELL STRUCTURES
   WITHIN THE LINE.  ILN VWP DERIVED HODOGRAPH SUGGESTS A 0-1KM SRH AOA
   290 M2/S2.  SUSPECT THAT THE STRONGEST POTENTIAL FOR TORNADOES WILL
   EXIST WITH MORE DISCRETE STRUCTURES THAT MANAGE TO THRIVE WITHIN THE
   EXPANDING LINEAR MCS.  OTHERWISE...DMGG WIND GUSTS WILL PROBABLY
   BECOME MORE OF AN ISSUE WITH TIME TONIGHT AS THE STORMS TRANSLATE
   DOWNSTREAM INTO SRN OH AND CNTRL/BLUEGRASS REGION OF ECNTRL KY.
   
   ..RACY.. 10/19/2007
   
   
   ATTN...WFO...JKL...ILN...LMK...IND...
   
   39838509 40498447 40478355 40228322 39688314 39128332
   38248398 37408464 36908537 36828598 36978690