DENVER (AP) -- Thunderstorms hit the Denver area with a fury Thursday, flooding streets and underpasses and stranding drivers in stalled-out cars.

Rains and lightning also swept through southern Colorado. The U.S. Women's Open at the Broadmoor in Colorado Springs was suspended because of thunder and lightning.

North of Denver, in Boulder County, rain unleashed mudslides down mountainsides where a wildfire last fall burned away trees and other vegetation. The Daily Camera says law enforcement officials reported mud about 100 yards wide and 4 feet deep on a road west of Boulder.

Xcel Energy reports 28,000 customers in the Denver area lost power Thursday afternoon from the storms. A recorded message from company spokesman Mark Stutz reports power had been restored to all but 9,000 customers by 11 p.m.

Stutz says extra crews were working through the night to restore service, but the company expects power won't be restored to everyone until about 9 a.m. Friday.

Stutz says the outages were caused by downed wires and branches and trees that had fallen on power lines.

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