NASHVILLE, Ill. (KTVI) – Thunderstorms with heavy rains and tornadoes rattled the Chicago area and elsewhere in the Midwest, overtopping a dam Tuesday in southern Illinois, cutting power to hundreds of thousands, and even sending weather forecasters scrambling for safety. A woman in Indiana died after a tree fell onto a home.

Water overtopped a dam near Nashville, Illinois, sending first responders to the flooded area to make sure everyone got out safely, officials said. There were no reports of injuries in the community of 3,000 southeast of St. Louis, but crews were sent to a home where a woman reported water up to her waist, said Alex Haglund, a spokesperson for the Washington County Emergency Management Agency.

Earlier, the Washington County Emergency Management Agency EMA advised residents south of the Nashville City Reservoir, located outside St. Louis, Missouri, to evacuate their homes immediately. Residents were told the community center in Nashville was open for shelter.

“The Failure of the Nashville dam is imminent. Please evacuate your home at this time. If you are in the grey box, you need [to] evacuate now!” the agency said Tuesday morning, referring to the shaded area of an online map.

EMA spokesperson Alex Haglund said a portion of the dam failed early Tuesday, but it wasn’t clear if it was a break or an overtopping. A “secondary failure” happened later in the morning when the dam was overtopped.

The National Weather Service also announced Tuesday morning that Washington and Clinton County have upgraded from a flash flood warning to a considerable flash flood.

The upgrade, according to the National Weather Service, means the flash flooding is a more dangerous situation than usual.

The National Weather Service said 5-7 inches (12.7-27.8 centimeters) of rain fell over an eight-hour period. Additional heavy rain was in the forecast. An 11-mile stretch of Interstate 64 in the Nashville area was closed because of flooding.

“We did have an area of rotation,” meteorologist Zachary Yack said, referring to extreme rotating wall clouds. “And it kind of developed right near our office here in Romeoville, Illinois. … We went and took cover. We have a storm shelter here.”

A 44-year-old woman died in Cedar Lake, Indiana, in the southern fringes of the Chicago area, the Lake County coroner’s office said.

Additionally, U.S. Highway 50 in Lebanon, Illinois, between State Route 4 and Belleville, Illinois, has been closed due to the flooding.

Illinois State Police say they have responded to three property damage crashes in the Washington County area. It is unknown if these crashes are flood-related.

The Associated Press contributed to this report.