Flash flooding hits Milwaukee as heavy rain pummels millions across the Midwest

More than 10 million people across the Midwest remain under flood alerts Monday morning as heavy rainfall continues to pummel parts of Wisconsin, Oklahoma, Kansas and Missouri, triggering flash flooding in Milwaukee that has forced the Wisconsin State Fair to cancel its last day.

So much rain fell in Wisconsin Saturday into Sunday that it could set a new state record. A rain gauge in northwest Milwaukee recorded 14.5 inches of rain over a 24 hour period, according to the Milwaukee Metropolitan Sewerage District. If confirmed by the National Weather Service, it would surpass the previous record of 11.92 inches set in Mellen, a town in northern Wisconsin, in 1946.

Milwaukee County declared a state of emergency Sunday as the Milwaukee River crested to a record 11.19 feet, topping the previous high of 10.48 feet set in July 2010. Floodwaters swamped roads, stranded vehicles, and prompted dozens of water rescues.

“It’s something that Milwaukee hasn’t seen in perhaps a decade or more,” Milwaukee Mayor Chevy Johnson said at a Sunday news conference, noting his own family was affected.

The region’s beloved Wisconsin State Fair was forced to shut down early on Saturday, canceling a performance by famed rock band Lynyrd Skynyrd. Organizers canceled its final day Sunday after rains flooded the fairgrounds in West Allis, just outside Milwaukee.

USA Triathlon also canceled its Sprint National Championships and Paratriathlon National Championships Sunday in Milwaukee due to flooding and damage on the course, the organization said. The flooding also hit Milwaukee Mitchell International Airport, where runways, taxiways and an underpass tunnel were flooded, the weather service said.

A flood warning remains in effect for Milwaukee until at least 10 a.m. Monday, as streams continue to rise, according to the National Weather Service.

Much of southern Kansas, part of western Missouri, and part of northern Oklahoma are under a Level 3 of 4 risk of flooding rain through Monday morning, according to the Weather Prediction Center. A Level 2 of 4 risk of flooding rain remains in place for a large swath of the Midwest, including southern Wisconsin, western Illinois, eastern Iowa, Missouri, Kansas, eastern Colorado and northern Oklahoma.

The severe weather is part of the same storm system that brought strong winds with gusts over 80 mph to Nebraska Saturday, where one person was killed and another was seriously injured by a large cottonwood tree that toppled onto their vehicle.

Hundreds of inmates at the Nebraska State Penitentiary had to be relocated after storms damaged two housing units, with no injuries reported, according to the Associated Press.

On Sunday, the Milwaukee Fire Department performed about 65 water rescues, working their way around “hundreds of vehicles around the city blocking intersections, making progress absolutely impossible,” Milwaukee Fire Chief Aaron Lipski said. A dozen fire departments from neighboring counties assisted with the response to the high number of calls, Lipski said.

Brian Baxter, whose two teenage daughters were home alone near the Menomonee River Parkway, described feeling “helpless” as floodwaters entered the family home as they waited to be rescued, he told CNN affiliate WDJT.

The girls, Brailey and Brecken, called their parents in the middle of the night as water rose, sharing with them a video of the flooding. They drove back home but were unable to reach their daughters as floodwaters had covered the neighboring streets. Rescue crews eventually retrieved the girls and their family dog.

Heavy rain will shift east into the Ohio Valley and Great Lakes through Monday, with lighter showers lingering in Wisconsin and the central Plains. Even with lower totals than Sunday, additional rain could still trigger flooding. Much of the Midwest will turn drier and cooler by midweek before another round of storms develops late in the week.

This story has been updated with additional information.

CNN’s Lauren Mascarenhas and Allison Chinchar contributed reporting

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