Severe threat update

MESOSCALE DISCUSSION 0770NWS STORM PREDICTION CENTER NORMAN OK0948 AM CDT FRI MAY 02 2008AREAS AFFECTED...PARTS OF ERN IL INTO MUCH OF INDIANACONCERNING...SEVERE POTENTIAL...WATCH LIKELY VALID 021448Z - 021645ZAN ADDITIONAL WW OR WWS WILL PROBABLY BE NEEDED LATER THISMORNING/AFTERNOON...PRIMARILY FOR AN INCREASING SEVERE THREATASSOCIATED WITH A DEVELOPING SQUALL LINE. PRIMARY THREAT APPEARS TOBE DAMAGING WINDS...BUT HAIL/ISOLATED TORNADOES ARE ALSO POSSIBLE.FORCING ASSOCIATED WITH AN IMPULSE PIVOTING AROUND THE EASTERNPERIPHERY OF THE CLOSED LOW OVER NEBRASKA APPEARS TO BE CONTRIBUTINGTO THE REINTENSIFICATION OF THE NORTHERN FLANK OF THE MIDDLEMISSISSIPPI VALLEY SQUALL LINE...NOW OVER CENTRAL/SOUTHERN ILLINOIS. THE INFLUENCE OF THIS FORCING LIKELY WILL DIMINISH LATER THISMORNING AS THE IMPULSE CONTINUES NORTHWARD TOWARD THE UPPERMISSISSIPPI VALLEY. BUT...DESTABILIZATION ASSOCIATED WITH AT LEASTWEAK HEATING AND LOW-LEVEL MOISTURE ADVECTION THROUGH THE LOWER OHIOVALLEY PROBABLY WILL MAINTAIN DEVELOPMENT AND FURTHERINTENSIFICATION BENEATH BROADLY DIFLUENT CYCLONIC UPPER FLOW. THISWILL OCCUR WITHIN A SHEARED 40-50 KT DEEP LAYER SOUTHWESTERLY MEANENVIRONMENT FLOW REGIME...AHEAD OF A 90 KT 500 MB JET STREAK NOWNOSING ACROSS THE OZARK PLATEAU. FAST MOTION OF CONVECTIVE SYSTEMIS EXPECTED TO CONTRIBUTE TO DAMAGING WIND POTENTIAL... PARTICULARLYAS ITS ASSOCIATED SURFACE COLD POOL BECOMES BETTERESTABLISHED/STRENGTHENS. AND...THIS COULD AFFECT INDIANAPOLIS ANDADJACENT AREAS OF CENTRAL INDIANA BY AROUND 18Z...KERR.. 05/02/2008...PLEASE SEE WWW.SPC.NOAA.GOV FOR GRAPHIC PRODUCT...ATTN...WFO...ILN...LMK...IWX...IND...PAH...LOT...ILX...LSX...