A stormy pattern will persist across the north-central United States with more severe weather expected through the start of July.

Hot, humid air centered over the nation's midsection will continue to provide fuel for violent thunderstorms to develop, intensify and maintain their strength for dozens of miles.

Into Sunday night, severe weather dangers are expected to arc from southeastern Montana and eastern Wyoming to southern Minnesota, Illinois and Indiana.

The violent thunderstorms halted racing at Chicagoland Speedway as a cluster of severe thunderstorms with damaging winds swept from southern Wisconsin to northern Illinois earlier on Sunday.

Lightning strikes in Chicago, Illinois, around 3:40 p.m. CDT, near the John Hancock Center skyscraper. (Twitter/@barrybutler9)

Around 4:30 p.m. CDT, there were three preliminary tornado reports from the National Weather Service's Storm Prediction Center. One tracked near Platte Creek while the others were reported in Gregory County.

One social media user caught a video of the tornado in Platte Creek, South Dakota, in the distance. As of Sunday afternoon, there have been no reports of damage.

A tornado tracked near Platte Creek, South Dakota, on Sunday afternoon around 4:30 p.m. CDT. As of Sunday afternoon, there have been no reports of damage. (Twitter/@HallieHallock)

By Sunday afternoon, over 300,000 customers were without power across the eastern half of the United States due to "large systems of scattered thunderstorms," according to a tweet from PowerOutages.us.

Around 156,713 customers in the Great Lakes region alone were without power as of 6 p.m. CDT, the majority of them in Illinois.

The strongest thunderstorms into Sunday night can produce wind gusts high enough to knock over trees and power lines, large, damaging hail and torrential downpours. An isolated tornado can also spin up.

It does not take a storm to be severe for it to produce potentially deadly lightning strikes.

Anyone with plans to be outside should make sure they keep a close eye to the sky and seek shelter indoors as soon as the sky darkens or thunder is heard.

If there is no other suitable option, a hard-top vehicle can also provide protection from dangerous lightning strikes.

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Even in the absence of severe weather, downpours accompanying the storms will make for poor driving conditions with reduced visibility and a heightened risk of hydroplaning while traveling at highway speeds. This includes sections of interstates 25, 29, 35, 80 and 90.

AccuWeather Senior Meteorologist Jack Boston expects a similar pattern to remain in place this week, leading to additional thunderstorm complexes rumbling through the North Central states, including during the July Fourth holiday.

The severe weather threat on Monday will extend from northeastern New Mexico and neighboring parts of Texas to southern Minnesota and Wisconsin. Once again, Minneapolis will be at risk.

The ongoing severe weather follows the severe storms that targeted the Dakotas, with a tornado reported southwest of Allen, South Dakota.

Late this past week, Montana and portions of the Midwest were hit with hail and wind damage from severe storms.

Download the free AccuWeather app to stay aware of the latest severe weather watches and warnings. Keep checking back for updates on AccuWeather.com and stay tuned to the AccuWeather Network on DirecTV, Frontier and Verizon Fios.

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