Derecho is unlikely to make it past Ohio. The CAPE will be high but not that high (2500 versus 5000 last year). The 850 temperatures over the area (WV mountains into DC will be 18-20C) Last year's derecho they were 24. That's most important over the mountains because without a good supply of warm air aloft the mountains will tear the storm up.
forecast maps: http://weather.unisys.com/gfs/gfs.php?inv=0&plot=850®ion=us&t=36h
I should also mention that the dynamics have to be just right. No old boundaries around to break up the system. That said, there are strong dynamics from a larger low moving through. That will create some strong storms with gusts here and there. Just no large MCS to take out power in 5 or 6 states.