MESOSCALE DISCUSSION 1176 NWS STORM PREDICTION CENTER NORMAN OK 0459 PM CDT FRI JUN 15 2012 AREAS AFFECTED...NCNTRL NEB AND CNTRL SD CONCERNING...SEVERE THUNDERSTORM WATCH 395... VALID 152159Z - 152330Z THE SEVERE WEATHER THREAT FOR SEVERE THUNDERSTORM WATCH 395 CONTINUES. SUMMARY...A SEVERE THREAT WILL MOVE GRADUALLY ENEWD ACROSS NRN NEB AND INTO CNTRL SD EARLY THIS EVENING. LARGE HAIL AND ISOLATED WIND DAMAGE WILL BE THE PRIMARY THREATS AND WW ISSUANCE WILL BE NEEDED TO THE EAST OF WW 395. DISCUSSION...A CLUSTER OF STRONG TO SEVERE THUNDERSTORMS IS ONGOING JUST SOUTH OF THE RAPID CITY AREA IN A POCKET OF MODERATE INSTABILITY WHERE MLCAPE IS ESTIMATED IN THE 1000 TO 2000 J/KG RANGE. IN ADDITION TO THE INSTABILITY...THE WSR-88D VWP AT RAPID CITY SHOWS STRONG DIRECTIONAL SHEAR BELOW 3 KM WITH 40 KT IN THE MID-LEVELS. THE STRONG VERTICAL SHEAR WILL BE FAVORABLE FOR SEVERE STORMS AND A SUPERCELL OR TWO MAY DEVELOP AS STORMS MOVE NEWD EARLY THIS EVENING. STEEP MID-LEVEL LAPSE RATES WILL BE SUFFICIENT FOR LARGE HAIL. LAPSE RATES ARE ALSO VERY STEEP AT LOW-LEVELS WITH 0-3 KM LAPSE RATES ESTIMATED ABOVE 9.0 C/KM ACROSS MUCH OF CNTRL SD. THIS MAY HELP THE WIND DAMAGE TO INCREASE EARLY THIS EVENING. ..BROYLES/CARBIN.. 06/15/2012 ATTN...WFO...FSD...ABR...LBF...UNR...CYS... LAT...LON 44650257 43630307 43010302 42480238 42360159 42490083 43009990 43429951 43959933 44929958 45090083 44650257
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