The storms caused "extensive damage to residential and commercial properties," and knocked down power lines, traffic lights, and trees throughout the area, the fire department said. By Sunday night, more than 17,000 people were without power — down from the nearly 82,000 people left in the dark Sunday morning, according to poweroutage.us.

More severe weather is expected in the Southern Plains Monday as residents in Oklahoma survey the destruction from tornado-spawning storms that injured at least 11 people and leveled homes over the weekend.

Severe weather remains a threat in parts of Oklahoma after strong storms and apparent tornadoes overnight ripped roofs off buildings and knocked out power to thousands of homes and businesses.