The outage struck at about 4:45 a.m., affecting 646 Pennsylvania Power Co. customers, said Randy Coleman, area manager for the utility. An electrical insulator that cracked during wind storms over the past week and broke free was the likely culprit, he said.

By 6:10 a.m. the utility switched the Hermitage commercial district over to another power supply and repairs began on the damaged electrical line. By 7 a.m. all but a dozen homes had their power restored and the utility expected those remaining homes to have power by noon, Coleman said.