NBC's John Yang reports on the extreme weather in the Midwest and East Coast.
The heat suffocating the Midwest is expanding east, forecasters said Thursday, as signs of the hot, muggy weather -- buckled roads -- have literally started to pop up.
"Record breaking heat across the Midwest is expected to spread into the eastern U.S. by the weekend," the National Weather Service warned -- bad news for the 600,000 homes and businesses still without power from Ohio to Virginia after last weekend's storms.
On top of that, storms overnight caused power outages to 250,000 homes and businesses in Michigan.
In Chicago, temps reached 103 degrees on Thursday before a sudden storm cooled the city with a downpour.
Atlanta reached 100 -- the third time so far this year.
More normal temperatures should return next week when the extreme heat is forecast to move west, bringing triple-digit temperatures to parts of Idaho, Utah, Washington and Oregon.
The storms were sandwiched between intense heat over the last two weeks. From Fargo, N.D., to Chicago and Cary, N.C., roads have heated up, drawing moisture underneath to the surface and then creating what's called a "heave."
In Wisconsin, the driver of an SUV didn't see a heave on Highway 29 near Eau Claire and went airborne, WISN-TV reported Tuesday. After getting several feet of air, the car sped out of control into oncoming traffic, and then plowed into a field.
Video camera captures a car leaping over a heat-buckled road near Eau Claire, Wisconsin. NO AUDIO
The driver and passenger were not seriously hurt.
Areas where roads buckled on July 4th included Chicago, where Columbus Drive was shut down, and Pennsylvania's Lancaster County, where crews deployed in the heat after a heave forced the closure of Route 222.
"I'd rather be at home, drinking my beer, eating a burger," state transportation worker Kevin Palumbo told NBC affiliate WGAL-TV. "We just try to get it done and get it over with."
But he was also aware of the danger of buckled roads. "It's a hazard," he said. "You don't want to hit that on your motorcycle at 80 miles an hour."
Travis Long / The News & Observer via AP
Workers wait for asphalt to arrive after removing a section of westbound I-440 that buckled in triple-digit temperatures on June 29 near Cary, N.C.
Buckled roads were just some of the frustrations still facing millions on Thursday.
In Chicago, soaring temperatures forced 17 public schools without air conditioning to cancel summer classes on Thursday, NBCChicago.com reported. Additional closures are possible in the days to come.
The Mid-Atlantic region was also struggling to get back to normal after the deadly storms.
Utility and municipal crews worked through the July 4th holiday to restore power and remove downed tree limbs. Officials blamed the storms for 26 deaths.
More than 2 million customers at one point lost power from the storms that converged on Maryland, Virginia, West Virginia, Washington, D.C., Indiana, Ohio and New Jersey on Friday. They packed winds topping 80 mph in some places, uprooting trees and damaging homes.
Much of the damage to the power grid was blamed on last weekend's rare "derecho," a big, powerful and long-lasting wind storm that blew from the Midwest to the Atlantic Ocean.
Pepco said it had restored power to 90 percent of those affected by last week's storms in D.C. and two Maryland suburbs, beating its own estimate for getting the air conditioning back on. BGE said about 78,000 customers in central Maryland remained without power.
More than 146,000 Virginia homes and businesses remained without power, down from a peak of about 1.2 million after the storms.
In New Jersey, Atlantic City Electric said nearly 30,000 homes and businesses were still without service. That's down from about 206,000.
Workers in Anchorage, Alaska, are still working to clear snow from last winter's record snowfall. KTUU's Ted Land reports.
While the number without power was diminishing Thursday utilities were not moving quickly enough for many of those still in the sweltering dark.
Many expressed frustration with handwritten messages hung from utility poles resembling "Wanted" posters, The Washington Post reported.
Along Route 29 in Silver Spring, Maryland, on Wednesday, a woman hammered a series of signs into non-functioning utility pole reading: "5 Days No Lite."
"Pepco: very warm humans feeling forgotten," read another sign, according to the paper.
Maryland issued a heat advisory for the entire state for Thursday, after issuing one for parts of the state for Wednesday.
The Associated Press and Reuters contributed to this report.
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