SPC MESOSCALE DISCUSSION 0786 FOR CNTRL/SRN WV
CONCERNING...SEVERE THUNDERSTORM POTENTIAL...

VALID 182220Z - 182330Z

BOW ECHO DEVELOPING OVER EXTREME SERN OH OVER GALLIA COUNTY IS
EXPECTED TO CONTINUE EWD INTO SWRN LOWLANDS OF WV DURING THE NEXT
COUPLE OF HOURS.  ADDITIONAL STORMS WILL ALSO MOVE ACROSS THE
REMAINDER OF CNTRL/SRN WV DURING THE EVENING.  DAMAGING WINDS WILL
BE THE PRIMARY THREAT ALONG WITH HEAVY RAINFALL AND MAYBE A BRIEF
ISOLD TORNADO.

ISOLD SUPERCELL AHEAD OF THE BOW ECHO OVER MASON/JACKSON COUNTIES
IN WV APPEARS TO HAVE WEAKENED SOMEWHAT SINCE 2200 UTC BUT WILL
CONTINUE TO HAVE A DAMAGING WIND/LARGE HAIL THREAT AS IT TRACKS
ACROSS SRN JACKSON COUNTY.  OTHERWISE...BOW ECHO...LIKELY PRODUCING
WIND DAMAGE...IS CROSSING THE OH RIVER AT 45 KTS.  EXTRAPOLATION
WOULD TAKE THIS FEATURE INTO CNTRL WV BY 0000 UTC WITH WIND DAMAGE
POTENTIAL INCREASING FROM MASON COUNTY EWD TO ROANE COUNTY.

CRW VWP SHOWS SUFFICIENT DEEP LAYER SHEAR...ON THE ORDER OF 35
KTS...AND IS SUFFICIENT FOR SUPERCELLS.  0-3 KM SRH DERIVED FROM
THE CRW HODOGRAPH USING MVMT OF THE ISOLD SUPERCELL NOW OVER MASON
COUNTY IS IN THE 150-200 M2/S2 RANGE.  GIVEN POCKET OF MLCAPE OF
1500 J/KG ALONG AN OUTFLOW BOUNDARY SITUATED ACROSS THE SWRN
LOWLANDS OF WV...STORMS MAY CONTINUE TO PRODUCE WIND DAMAGE/ISOLD
TORNADOES DURING THE NEXT COUPLE OF HOURS.  STORMS WILL LIKELY
WEAKEN AFTER SUNSET AND AS THEY MOVE OUT OF THE MOST UNSTABLE
AIRMASS OVER THE OH VLY.

..RACY.. 05/18/01