ZCZC SPCSWOMCD ALL ACUS11 KWNS 112328 SPC MCD 112328 MTZ000-WYZ000-120100- MESOSCALE DISCUSSION 0878 NWS STORM PREDICTION CENTER NORMAN OK 0628 PM CDT SAT JUN 11 2016 AREAS AFFECTED...PORTIONS OF ERN MT AND FAR NRN WY CONCERNING...SEVERE THUNDERSTORM WATCH 246... VALID 112328Z - 120100Z THE SEVERE WEATHER THREAT FOR SEVERE THUNDERSTORM WATCH 246 CONTINUES. SUMMARY...THE SVR RISK CONTINUES ACROSS WW 246. DISCUSSION...A CLUSTER OF STRONG TO SVR TSTMS IS SPREADING NWD ACROSS PORTIONS OF SERN MT. THIS ACTIVITY FORMED WITHIN THE DEEP BOUNDARY LAYER ACROSS NERN WY AND SERN MT...AND IS PRESENTLY ENTERING A CORRIDOR OF RELATIVELY RICH LOW-LEVEL MOISTURE FOR THESE ELEVATIONS. SFC OBS AT GLENDIVE...BAKER...AND MILES CITY INDICATE LOWER/MIDDLE 60S DEWPOINTS EXTENDING INTO E-CNTRL MT...FOSTERING STRONG INSTABILITY OWING TO A STEEP OVERLYING MID-LEVEL LAPSE RATE PLUME. AS CONVECTION SPREADS NWD DURING THE NEXT FEW HOURS...IT WILL LIKELY CONTINUE TO INTENSIFY. GIVEN 50-65 KT OF MID-LEVEL FLOW SAMPLED BY THE BLX VWP...AMPLE DEEP SHEAR WILL SUPPORT SUSTAINED UPDRAFTS CAPABLE OF SVR HAIL -- SOME POSSIBLY SIGNIFICANT. AMALGAMATING COLD POOLS COULD LOCALLY ENHANCE THE SVR-WIND RISK AS CONVECTION SPREADS NWD THROUGH PARTS OF CUSTER COUNTY AND INTO PRAIRIE...DAWSON...AND MCCONE COUNTIES IN THE NEXT FEW HOURS. WHILE AMPLE LOW-LEVEL DIRECTIONAL SHEAR AIDED BY BACKED LOW-LEVEL FLOW MAY SUPPORT A BRIEF TORNADO RISK...SIZABLE TEMPERATURE DEWPOINT SPREADS MAY TEND TO ENCOURAGE MORE OUTFLOW-DOMINANT CONVECTION. OTHER TSTM DEVELOPMENT IS ONGOING FROM W OF BILLINGS TOWARD THE BIG HORN MOUNTAINS...IN ASSOCIATION WITH ASCENT ACCOMPANYING THE RIGHT-ENTRANCE REGION OF A HIGH-LEVEL SPEED MAX GRAZING THE AREA. THIS ACTIVITY MAY CONTINUE TO INCREASE IN COVERAGE AND INTENSITY AND SPREAD NWD/NNEWD ACROSS WRN PARTS OF THE WATCH AREA...POSING PRINCIPALLY A SVR HAIL RISK WITH LOCALLY SVR WIND GUSTS POSSIBLE. ..COHEN.. 06/11/2016 ...PLEASE SEE WWW.SPC.NOAA.GOV FOR GRAPHIC PRODUCT... ATTN...WFO...BYZ...GGW... LAT...LON 45110783 45770812 47890801 48770716 48780491 48010416 45510433 45010602 44740711 45110783 NNNN