MESOSCALE DISCUSSION 1093 NWS STORM PREDICTION CENTER NORMAN OK 0136 PM CDT THU JUN 07 2012 AREAS AFFECTED...N-CNTRL/CNTRL/S-CNTRL NORTH DAKOTA CONCERNING...SEVERE POTENTIAL...WATCH POSSIBLE VALID 071836Z - 072030Z PROBABILITY OF WATCH ISSUANCE...40 PERCENT SUMMARY...A THREAT FOR SVR THUNDERSTORMS MAY INCREASE THIS AFTERNOON ACROSS N-CNTRL/CNTRL/S-CNTRL ND. TRENDS WILL CONTINUE TO BE MONITORED...AND A WW MAY BE NEEDED THIS AFTERNOON. DISCUSSION...LATEST SFC MESOANALYSIS DEPICTS A STATIONARY FRONT EXTENDING N-S OVER THE WRN HALF OF ND. ALONG THIS FRONT LIES A SFC LOW SW OF BISMARCK...WITH A WARM FRONT EXTENDING E OF THE LOW. LOW-LEVEL MASS FLUX INTO WRN ND ON THE NOSE OF A MODEST LOW-LEVEL JET CONTINUES SUPPORTING SCATTERED ELEVATED CONVECTION WEST OF THE STATIONARY FRONT. THIS ACTIVITY MAY POSE A HAIL THREAT INTO THE AFTERNOON AS INFLOW INTO THIS ACTIVITY DESTABILIZES. EAST OF THE STATIONARY FRONT...INSOLATION/DIBABATIC HEATING ON EITHER SIDE OF THE WARM FRONT MAY AID IN ITS NWD MOTION WITH MLCAPE VALUES INCREASING TO 1000-2000 J/KG AS SFC DEWPOINTS HOLD IN THE LOWER 60S. THIS MAY SUPPORT SFC-BASED CONVECTIVE INITIATION EAST OF THE STATIONARY FRONT BY LATE AFTERNOON...POSSIBLY EVOLVING FROM THE WNW-ESE-ORIENTED ARC OF ELEVATED CONVECTION CURRENTLY CROSSING THE STATIONARY FRONT NEAR THE LOW. HOWEVER...IT MAY TAKE AT LEAST A FEW HOURS FOR STRONG ANTECEDENT SFC-BASED INHIBITION TO ERODE PER A MODIFIED 12Z BISMARCK SOUNDING...WITH AROUND 100 J/KG OF SBCINH REMAINING AS OF EARLY AFTERNOON. A ZONE OF ENHANCED SLY MID-LEVEL FLOW OVER THE ERN PERIPHERY OF A WRN CONUS LONGWAVE TROUGH WILL BE ASSOCIATED WITH 25-35 KT OF EFFECTIVE BULK SHEAR...WHICH MAY SUPPORT OCCASIONALLY ORGANIZED STORM STRUCTURES AND PERHAPS TRANSIENT SUPERCELLS WITH ANY SFC-BASED CONVECTION. SVR HAIL/WIND WILL BE THE MAIN CONCERNS WITH THIS ACTIVITY...THOUGH A WEAK/BRIEF TORNADO CANNOT BE RULED OUT NEAR THE AFOREMENTIONED SFC BOUNDARIES/LOW. ..COHEN/WEISS.. 06/07/2012 ATTN...WFO...FGF...BIS...
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