ZCZC SPCSWOMCD ALL ACUS11 KWNS 161708 SPC MCD 161708 VAZ000-PAZ000-MDZ000-DCZ000-WVZ000-OHZ000-161845- MESOSCALE DISCUSSION 0950 NWS STORM PREDICTION CENTER NORMAN OK 1208 PM CDT THU JUN 16 2016 AREAS AFFECTED...CNTRL/ERN OH...SWRN/SRN PA...NRN WV...MD...NRN VA CONCERNING...SEVERE POTENTIAL...WATCH LIKELY VALID 161708Z - 161845Z PROBABILITY OF WATCH ISSUANCE...95 PERCENT SUMMARY...THREAT FOR WIDESPREAD STRONG TO DMGG WINDS AND ISOLATED LARGE HAIL WILL INCREASE OVER THE NEXT 1-2 HRS FROM ERN OH SEWD ACROSS SWRN PA AND NRN WV. THESE THREATS WILL EVENTUALLY EXTEND EWD ACROSS NRN VA AND MD LATER THIS AFTERNOON. A WATCH WILL LIKELY BE ISSUED BY 18-19Z. DISCUSSION...ISOLATED TSTMS HAVE DEVELOPED NEAR/SE OF CLEVELAND OVER THE PAST 1-2 HRS...ALONG WHAT APPEARS TO BE A PRE-FRONTAL WIND SHIFT EXTENDING SWWD INTO W-CNTRL OH. PRIMARY SFC LOW IS CENTERED OVER WRN LAKE ERIE...WITH COLD FRONT ENTERING NWRN OH AS OF 16Z. STRONG SFC HEATING IS OCCURRING ACROSS CNTRL AND ERN OH AHEAD OF THE DEVELOPING CONVECTION...AND UPPER 60S TO LOWER 70S F DEWPOINTS ARE CONTRIBUTING TO MLCAPE VALUES LIKELY APPROACHING 2000 J/KG. CONVECTIVE COVERAGE SHOULD CONTINUE INCREASING THROUGHOUT THE EARLY AFTERNOON ACROSS CNTRL/ERN OH...WITH A QUICK EVOLUTION INTO CLUSTERS/LINE SEGMENTS PRIOR TO UPSCALE GROWTH INTO A LIKELY MCS. CONVECTION PERSISTING ACROSS WRN PA AND NERN WV HAS RESULTED IN EFFECTIVE BAROCLINIC ZONE FROM E-CNTRL OH INTO NRN WV...BUT CLEARING/SUBSIDENCE IN THE WAKE OF ONGOING CONVECTION SHOULD ALLOW FOR AT LEAST PARTIAL AIR MASS RECOVERY. PRIMARY THREAT IS LIKELY TO BE DMGG WIND GUSTS WITH EVOLVING CONVECTIVE SYSTEM...BUT ISOLATED LARGE HAIL IS ALSO POSSIBLE. MODERATELY STRONG WLY LOW-MIDLEVEL FLOW WAS OBSERVED IN PBZ/CLE VWP DATA...AND VEERING WITHIN THE LOWEST 1 KM AGL MAY SUPPORT THE POTENTIAL FOR A TORNADO OR TWO...PARTICULARLY WHILE CONVECTION REMAINS MORE DISCRETE. TRENDS ARE BEING CLOSELY MONITORED FOR ISSUANCE OF A WW...LIKELY BY 18-19Z. ..ROGERS/GOSS.. 06/16/2016 ...PLEASE SEE WWW.SPC.NOAA.GOV FOR GRAPHIC PRODUCT... ATTN...WFO...AKQ...CTP...LWX...PBZ...RLX...CLE...ILN... LAT...LON 40598246 41418146 41688098 40767980 39917721 39247649 37867628 38417988 39098286 40018330 40598246 NNNN