Thousands of Western Pennsylvanians remain without power today and might not have service restored until Sunday morning.

Wednesday’s brief but powerful thunderstorm has left a lasting impression.

Duquesne Light reported 13,000 customers — many in Allegheny County’s South Hills neighborhoods — do not have electricity. Customers in Baldwin, Castle Shannon, Dormont, Mt. Lebanon and Scott, as well as Banksville, Beechview and Brookline in the city, might not have service until Sunday, said spokesman Joseph Vallarian.

Allegheny Power reported 14,000 Pennsylvania customers were in the dark. Those in Allegheny, Washington and Westmoreland counties might not have service restored until 11:30 p.m. Friday, the company said.

High winds and lightning yesterday afternoon toppled trees, power lines and even an old church steeple, damaging homes, businesses and cars and prompting schools to cancel classes today. About 30 businesses and schools closed or delayed opening, according to WPXI-TV, the Tribune-Review’s news partner.

A generator leaking carbon monoxide forced the evacuation of a Mt. Lebanon apartment building early this morning, a spokeswoman with the township said. No one was injured.

Fourteen people who live in the lower levels of the building on Washington Road took refuge in the nearby municipal building, the spokeswoman said. Their apartments were ventilated, and residents returned about 7 a.m., she said.

Emergency dispatchers fielded calls of sparking electrical wires, downed trees and a transformer fire this morning in Pittsburgh.

Hilltop Road from Breckenridge Drive in Collier to Collier Avenue in Heidelberg was closed because of downed lines and trees, PennDOT said.

Wind gusts estimated at nearly 70 mph sent trees crashing onto cars in Mt. Lebanon and Banksville, according to National Weather Service reports and emergency dispatchers. Small hail was reported across the South Hills, the weather service said.

About 100,000 Duquesne Light and Allegheny Power customers lost power at the height of the storm.

Lightning shattered the steeple at a former South Side church housing the Pittsburgh Action Against Rape offices, sending the wooden, brick and copper structure through the roof and ceilings of the three-story building on South 19th Street.

“There’s a steeple on my chair,” said Leah Vallone, the center’s supervisor of crisis intervention, who escaped injury because she was in a meeting. “I was religious, but I think I will be even more so now.”

Five employees of the Lighting by Erik showroom on West Liberty Avenue in Dormont escaped injury when a window exploded under the force of the wind, shards of glass turning into shrapnel as dozens of chandeliers, lamps and glass accessories inside shattered.

“The windows were just shaking and rattling,” said Lewis Cantor, whose family has owned the business since 1965.

Westmoreland 911 dispatchers had reports of homes with structural damage, and downed trees and wires, said spokesman Dan Stevens. He said Greensburg, Unity, Penn and Murrysville as some of the hardest-hit areas.

“I was sitting there, watching the storm, and then all of a sudden the wind became so terrific, and this tree just cracked, and it fell straight in my yard. It missed my house, but it came close,” said Jack Zellie of Unity in Westmoreland County. “It happened suddenly. A great, big wind came up it seemed like a wind burst of sorts you could see (the tree) just crack. … It was overwhelming, to be honest with you.”

Damage reports continued to come in this morning, Stevens said.

“This was a fast-moving, widespread storm,” he said. “People made it home last night and just didn’t go back out.

“They’re just going out now and finding that there are trees down in their roads.”

Staff writers Cody Francis contributed to this report.