I-94 derecho

The I-94 derecho was a wind storm that occurred on July 19, 1983, with Minnesota and Wisconsin in its axis.

North Dakota

It began as a storm system in Montana and hit North Dakota at 7 a.m. CDT. Minot reported winds up to 70 mph.

Minnesota

The storm then moved into Minnesota. Winds up to 100 mph were recorded at the Alexandria Airport. It arrived in Minneapolis at 4 p.m. CDT and left 250,000 people without power.

Wisconsin

The derecho then moved into Wisconsin. A meteorologist working at the University of Wisconsin-Madison saw the derecho's approach. Windows were blown out at the campus.

Illinois

The derecho moved into Illinois at 9 p.m. CDT. Chicago had winds gusting to 70 mph and dropped 14°F (from 83°F at 9:30 p.m. to 68°F at 9:50 p.m.). The storm died in northwestern Indiana at midnight on July 20.