ZCZC MKCSWOMCD ALL;343,0864 403,0825 363,0825 303,0864; ACUS3 KMKC 182313 MKC MCD 182313 SELS MESOSCALE DISCUSSION FOR ...ERN KY/ERN TN/NERN AND CNTRL AL/NRN GA... CONCERNING...SEVERE THUNDERSTORM POTENTIAL... SVR WX/TORNADO OUTBREAK HAS BEEN IN PROGRESS ACRS PTNS OF THE LWR OH AND TN VLYS INTO THE LWR MS VLY DURG THE PAST 3 TO 4 HRS. ACTVTY IS OCRG IN A RGN OF VERY UNSTBL AIR AND STG SPD SHEAR. LTST MDL DATA FROM THE RAPID UPDATE CYCLE SUGGESTS THAT THE ACTVTY WILL BE MOVG EWD DURG THE NXT 3 TO 6 HRS EXTDG ALG THE WRN SIDE OF THE APPALACHIAN CHAIN WITH HELICITY VALUES BTWN 300 AND 400 M2/S2. WE ARE CURRENTLY MONITORING AREAS FM CNTRL AND ERN AL INTO NRN GA FOR PSBL WW. ..MCCARTHY.. 05/18/95