National Weather Service Chicago confirms tornado Sunday in Grayslake, Illinois

GRAYSLAKE, Illinois -- After assessing damage on Monday, August 3rd from storms that rolled through Wisconsin and into Illinois on Sunday, the National Weather Service has now confirmed a tornado in Illinois.

On Twitter Monday, the National Weather Service said storm damage in the Grayslake, Illinois area is tornado damage.

A National Weather Service Survey Team was on site Monday.

No EF rating has been assigned to this tornado yet.

The storms Sunday led to a Severe Thunderstorm Watch and several Severe Thunderstorm Warnings beginning Sunday evening in southeastern Wisconsin.

There were Tornado Warnings in Chicago on Sunday night:

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Meanwhile, one person was killed and at least 15 were injured Sunday when hail and high winds uprooted a tent at a festival west of Chicago, authorities said.

The incident happened at around 2:40 p.m. local time (3:40 p.m. ET) at the Prairie Fest in Wood Dale, Illinois.

Organizers of Lollapalooza said Sunday afternoon in a news released they'd be shutting down the music festival for "a short period" due to the weather. They directed those in attendance to underground shelter sites along Michigan Avenue.

A second release said gates would reopen at 3:30 p.m. and the music would resume at 4 p.m.