Severe thunderstorms, tornadoes threaten Midwest; sweltering heat wave hits from Michigan to northern Florida

Thunderstorms and tornadoes are pulsing through parts of the upper Midwest on Wednesday as dangerous, sweltering heat bakes nearly a third of the nation's population.

Scattered severe thunderstorms, as well as several tornadoes, large hail and gusty, damaging winds are lining parts of Iowa into Wisconsin, according to NOAA’s Storm Prediction Center forecast. Heavy rainfall and scattered flash flooding are also possible in the region, according to the National Weather Service.

In parts of the central Plains, isolated thunderstorms are forecast by late afternoon Wednesday, the storm prediction center said.

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Some severe storms may also bring damaging winds and large hail Wednesday to the Southeast through the central Appalachians, the weather service forecast.

Line of damaging thunderstorms moves across Midwest

Central Iowa to the upper peninsula of Michigan is at the highest risk for damaging thunderstorms with the worst of the storms likely to hit north and west of Chicago on Wednesday evening, according to AccuWeather meteorologists.

Severe thunderstorms along with tornadoes continue to progress eastward of Wisconsin towards the east of Illinois.

The National Weather Service issued several severe thunderstorm and tornado warnings for west Wisconsin as parts of east Wisconsin received an all-clear for the remainder of Wednesday.

Thousands of Wisconsin residents are without power, according to various energy services. Mausten, Wisconsin, saw a tornado race through the city Wednesday afternoon.

"There is damage with lots of power lines down, lots of trees down. We got some damages to businesses that we have confirmed," city administrator Randy Reeg told USA TODAY on Wednesday. "We have unconfirmed reports of damage to our hospital. We know they were without power."

A spattering of tornado warnings were issued in the Chicago area earlier this week as severe thunderstorms and gusty winds rattled the Windy City on Monday.

The severe thunderstorm threat is expected to shift east Thursday, bringing large hail and the possibility of tornadoes into the eastern Great Lakes, upper Ohio Valley and the mid-Atlantic region, the storm prediction center said.

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YESTERDAY'S WEATHER: Sweltering heat stifling one-third of US population; severe storms leave thousands in dark

US swelters with record-breaking temperatures

A week of record-breaking heat continues to hit a wide swath of the nation, with excessive heat warnings and advisories remaining from Michigan to northern Florida, the National Weather Service said.

In Odessa, Texas, thousands of residents were left contending with high temperatures and no water after a water line broke Monday. The city has struggled for a second day to restore the line.

Dangerously hot and humid weather will persist Wednesday from the Upper Midwest to the Southeast, with many locations once again seeing triple-digit heat indices.

Daily high records were reached in part of Michigan and South Carolina.

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Extreme heat in Chicago; relief on the way

The central U.S. has suffered through several days of excessive heat with highs in the high 90s and low 100s, according to AccuWeather. Tuesday, Midway Airport in Chicago soared to 100 degrees for the first time since July 2012, AccuWeather said.

But cooler, less humid air Thursday may bring some relief to the region.

"Finally, by late in the week, a cold front will trim back the heat and bring some relief to portions of the Midwest and Great Lakes," AccuWeather senior meteorologist Dan Pydynowski said.

Still, the National Weather Service said much of the region will continue to see above-normal temperatures

Heat wave to bake West

Meanwhile, parts of the West should see a return of triple-digit, excessive heat by Thursday. Temperatures are forecast to climb well above normal across much of the Great Basin, Rockies and Southwest on Thursday, the National Weather Service said.

An excessive heat warning has been issued for parts of interior Southern California and Arizona, where daytime highs will once again soar well into the triple digits.

Contact News Now Reporter Christine Fernando at cfernando@usatoday.com or follow her on Twitter at @christinetfern.

This article originally appeared on USA TODAY: Severe thunderstorms in Midwest; heat wave blankets US