BEMIDJI, Minn. (AP/WCCO) — A strong storm with destructive winds has knocked down trees and power lines in Minnesota.

Tens of thousands of customers lost power from Duluth to the Twin Cities on what could be the hottest day of the year.

In Duluth, officials advised against travel early Thursday because of dangerous power lines and debris in the streets. Duluth Public Schools also closed for summer school, KEY zone, practices, lunch and latch key programs.

Gallery: Damage After July 21 Storms

In Beltrami County, crews were out clearing roads of debris. Sirens were sounded early Thursday when the National Weather Service warned of a thunderstorm with winds of up to 80 miles per hour. Sheriff’s officials say they have no reports of serious injuries.

Authorities urged citizens to take it slow when clearing debris because of the dangerous heat and humidity.

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