Several American cities experienced impressive tornadoes that destroyed many of their buildings, leaving residents without electricity for hours.

On Friday, the National Weather Service warned Americans of a high risk of tornadoes and severe thunderstorms, including in Kansas, Iowa, Missouri and Nebraska.

14 tornadoes were reported in Kansas and Nebraska Friday, according to the US Oceanic and Atmospheric Watch; The hurricane alone could have hit more than 900 buildings.

The cities of Wichita and Andover, Kansas, were hard hit; The mayor of Wichita said more than 50 buildings were damaged. As of yesterday, more than 22,000 users were without power.

On Twitter, a member of the Wichita Police Department urged people in the area not to travel to Andover due to the damage and emergency services workload. “Please don’t come to Andover unless you have to. And the emergency services want to focus on Andover families and not on people curious to see the damage.”

Historically, mid-April through mid-June in Kansas, the state nicknamed “Hurricane Alley,” had the highest frequency of tornadoes.

In 1991, the city of Andover suffered fatal tornadoes which injured 225 people and killed 17 others.