NASHVILLE, Tenn Strong winds and hail battered a swath of states through the Ohio Valley overnight, damaging cars and homes, knocking over trees and power lines, and spawning at least one tornado.
Tennessee and Pennsylvania appeared to bear the brunt of the bad weather, with reports of tornadoes in both states. But the storm hit portions of at least eight states, also including Indiana, Ohio, Kentucky, West Virginia, Virginia and North Carolina, according to a National Weather Service map.
The storm can be blamed on a competing mix of warm and cool temperatures across the Ohio Valley, said Paul Walker, senior meteorologist with AccuWeather.
"There was cold air clashing with the warm air, causing the atmosphere to be very unstable," he said.
A tornado touched down in southwestern Pennsylvania on Wednesday night, severely damaging dozens of homes and a high school auditorium where students were rehearsing a play, said Kurt Ferguson, manager of Westmoreland County's Hempfield Township.
About 40 houses in the area have been deemed uninhabitable, based on an initial damage assessment, he said. Some were essentially "blown apart," while others were badly damaged.
No serious injuries were reported due to the tornado, which touched down shortly before 6 p.m. local time, according to Ferguson.
On one road, as many as 50 trees had been uprooted and power lines had fallen, Ferguson said.
"We couldn't even get to all the areas affected," he said.
About 100 students were rehearsing a play in an auditorium at Hempfield Area High School when the tornado struck, ripping off part of the roof, he said. They were evacuated from the building safely, Ferguson said.
The National Weather Service determined that it was a low-grade, or F2, tornado, according to Dan Stevens, deputy emergency management coordinator for Westmoreland County.
"We went through an F2 tornado without one injury or one fatality," he said. "That's an amazing situation."
A fast-moving storm caused wind damage across a wide section of Tennessee on Wednesday night and included reports of 1.5-inch hail, according to emergency agencies.
Some of the most severe damage was to homes and buildings along a two-mile stretch in Wilson County, just east of Nashville.
"It looks tornadic to me," said John Jewell, the county's emergency management director. "I had one house that took a pretty good beating, had the back porch torn off, roof damage and siding damage."
Elsewhere in the state, three homes were destroyed in a rural area and a section of a building was blown into a roadway southeast of Nashville, blocking traffic, said Dean Flener, spokesman for the Tennessee Emergency Management Agency.
(Reporting and Writing by Colleen Jenkins; Additional reporting by Daniel Lovering in Pittsburgh and Tim Ghianni in Nashville; Editing by Greg McCune)