A rare and dangerous cluster of severe weather known as a "derecho" has left more than 700,000 people across the Midwest without power on Wednesday and taken at least three lives.

Tuesday's storms brought winds of more than 100 mph and devastating flooding across parts of Illinois, Indiana, Ohio, Kentucky and parts of West Virginia and Virginia.

In Portage, Indiana, one person died when a house exploded during the storms. While the cause of the explosion is still under investigation, neighbors told local media they had just stepped outside to check out the storm damage when the blast happened.

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A 4-year-old boy died when a tree fell on a home in Jennings County, Indiana, according to the Sheriff's Office there.

In Ohio, Gov. Mike DeWine said a resident of Roseville died during a health emergency when first responders, faced with flooded roads, couldn’t get there. He warned that flood dangers would persist.

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“This is not something that will end tonight,” DeWine said of the severe weather.

Lightning hits Ohio prison

Sixteen incarcerated people were hospitalized, including one who was flown by helicopter, after lightning struck at a prison complex southwest of Cleveland, according to the Ohio Department of Corrections. The victims were injured as they returned from an evening meal at Grafton Reintegration Center, department spokesperson JoEllen Smith said in an email Tuesday evening. Their conditions weren't immediately known.

Dayton, Ohio, set a daily rainfall record with 2.07 inches, shattering a mark set in 1915, the weather service said. Multiple rounds of rain would cause flood hazards in the Ohio Valley through early Friday.

One car on Interstate 71 near Columbus, Ohio, literally flipped when a strong gust of wind hit from the side. Traffic cam footage from the Ohio Department of Transportation captured the vehicle going airborne from the right lane over the left lane and into the median.

Tornadoes strike near Chicago

Two tornadoes touched down just south of Chicago, the National Weather Service said Tuesday night. Photos posted on social media from the Chicago area, and across the state line in Indiana, showed flooded roads, trees tangled in power lines and homes with gashes in their roofs.

“No power. It was very scary. We were down in the basement,” said Javid Jenkins of Homewood, a Chicago suburb. “We’re built for snow. We’re built for cold. We’re not built for this.”

Jenkins, 54, said he was driving around for gas to fire up a generator to preserve food in his refrigerator.

Tornado warning sirens howled as the skies darkened. All flights were temporarily stopped at Chicago’s two major airports, and officials warned of delays as the backlog was cleared.

Widespread damage in Indiana

On Wednesday morning, Indiana was reporting the largest number of power outages, with more than 300,000 customers without electricity after violent winds took down power poles.

A wind gust of 99 mph was recorded Tuesday at the Gary Chicago International Airport in Gary, Indiana.

The fifth day of the 10-day Lake County, Indiana, Fair was canceled, disappointing fans who were hoping to see a professional wrestling event involving people under 5 feet tall.

Nearby in LaPorte County, Indiana, there was a “tremendous amount of tree damage,” Commissioner Joe Haney said.

Threat is not over

The rainfall threat remains for many of these same areas on both Wednesday and Thursday, with a level 2 of 4 flood threat stretching from the Central Plains to the Appalachians. There is even a severe threat, where gusty winds and large hail are the main concern. 

The Associated Press contributed to this report.