MESOSCALE DISCUSSION 0546 NWS STORM PREDICTION CENTER NORMAN OK 1102 AM CDT THU MAY 13 2010 AREAS AFFECTED...IND...NRN KY THROUGH WRN AND CNTRL OH CONCERNING...SEVERE POTENTIAL...WATCH LIKELY VALID 131602Z - 131800Z STORMS ARE EXPECTED TO REDEVELOP AND INTENSIFY ACROSS THE OH VALLEY DURING THE AFTERNOON. DAMAGING WIND...LARGE HAIL AND ISOLATED TORNADOES WILL BE POSSIBLE. WW WILL LIKELY BE NEEDED BY 17Z. WARM FRONT EXTENDS FROM CNTRL WV NWWD THROUGH SRN OH...NRN IND AND NRN IL INTO SERN IA WHERE IT INTERSECTS A COLD FRONT THAT STRETCHES SWWD THROUGH MO. A COUPLE OF OUTFLOW BOUNDARIES WERE INDICATED IN IL MOVING EAST AHEAD OF THE COLD FRONT. AXIS OF MID TO UPPER 60S DEWPOINTS HAVE ADVECTED THROUGH THE WARM SECTOR. DIABATIC WARMING OF THE MOIST BOUNDARY LAYER IS DESTABILIZING THE ATMOSPHERE...WITH A RESERVOIR OF 1000-1500 J/KG MLCAPE INDICATED SOUTH OF WARM FRONT FROM CNTRL AND SRN IND AND NRN KY THROUGH SWRN OH. OUTFLOW BOUNDARY ACROSS ERN IL IS MOVING EAST AT 25-30 KT...AND SHOULD PROVIDE A FOCUS FOR ADDITIONAL STORMS TO DEVELOP AS IT ADVANCES THROUGH THE DESTABILIZING WARM SECTOR. THE MORNING RAOB FROM WILMINGTON OH INDICATED ONLY A MODEST CAPPING INVERSION AROUND 700 MB...AND SUGGESTS DISCRETE STORMS COULD ALSO DEVELOP IN WARM SECTOR AS THE BOUNDARY LAYER DESTABILIZES. A SWLY 45-50 KT LOW-LEVEL JET WILL MIGRATE NEWD THROUGH THE WARM SECTOR IN ASSOCIATION WITH NEWD EJECTING MID-UPPER LEVEL SPEED MAX. THIS WILL MAINTAIN FAVORABLE DEEP LAYER SHEAR AND SUFFICIENT LOW-LEVEL SHEAR FOR ORGANIZED STORMS INCLUDING BOW ECHOES AND SUPERCELLS WITH LOW-LEVEL MESOCYCLONES. ..DIAL.. 05/13/2010