The heat was to blame for at least 66 deaths across the U.S., where hundreds of thousands remain without electricity after severe storms last week. NBC's Michelle Franzen reports.
Updated at 8:36 p.m. ET: The heat that blanketed much of the U.S. began to ease up from unbearable to merely very hot Sunday as temperatures from the Midwest to the East Coast dropped from highs above 100 degrees down to the 90s.
Cooler air swept southward in the eastern half of the country, bringing down some temperatures by 15 or more degrees from Saturday's highs, which topped 100 in cities including Philadelphia, Washington, St. Louis, Indianapolis and Louisville, Ky.
For many areas, the cooler temperatures were ushered in by thunderstorms that knocked out power to thousands. In New Jersey, a line of strong, fast-moving storms knocked out power to nearly 70,000 on Saturday night.
The heat was blamed for at least 74 deaths across the country in the past two weeks, according to NBC News. A 4-month-old girl died and a 16-month-old girl was hospitalized in suburban Indianapolis after they were found Saturday trapped in separate cars during 105-degree heat. In Marion County, Ind., a 92-year-old man was found dead inside his home that was closed up and not ventilated and a 54-year old man was found dead outside near his residence in extreme heat on Saturday. And in New Jersey, a 48-year-old woman was struck and killed by lightning on Saturday night while walking along a sea wall with friends and family at a Monmouth County beach.
Temperatures in the 90s are a welcome relief after days when the mercury hit triple digits. But with cooler air comes a new threat – severe storms. The Weather Channel's Kelly Cass reports.
The heat wave has been near-unprecedented for several major cities, according to NBC News. In Chicago, the temperature reached 100 degrees for three consecutive days from Wednesday through Friday, which ties the records of July 3-5, 1911, and Aug. 4-6, 1947. St. Louis' streak of 10 consecutive days of 100 or higher (June 28 through July 7) has only been topped by the Dust Bowl year of 1936 when the streak was 13 days. In Minneapolis, the mercury hit triple-digits on Wednesday and Friday at the Twin Cities International Airport; the last year there were at least two 100-degree high temperatures in the Twin Cities was 1988, when there were four. And Washington hit 100 on Sunday for the fourth consecutive day, tying a record set July 19-22, 1930.
The heat caused highways to buckle in Illinois and Wisconsin, officials said. In Maryland, investigators said heat likely caused rails to kink and led a commuter train to partially derail Friday. No one was injured.
Forecasters warned that a new round of record highs could soon bake Western states.
"It's going to start as soon as tomorrow - really everybody in the Rockies is going to see this heat,'' said Alan Reppert, senior meteorologist for Accuweather.com. He said a high-pressure system developing over the Rockies will cause temperatures over 100 degrees Fahrenheit in Salt Lake City by Wednesday.
Celebrating the warm summer months, as schools let out and the cooling off begins
To stay cool, Americans tried familiar solutions — dipping into the pool, going to the movies and riding subways just to be in air conditioning.
Even the beach offered no respite. Atlantic City, N.J., home of the famed boardwalk, set a temperature record Saturday of 100 degrees.
Working outdoors in New Jersey on Saturday was Freddie Jackson, a 48-year-old Toms River man who sells roses by the dozen from his car, which was parked in a heavily shaded area off a major highway. Clad in shorts, sandals and a white T-shirt, Jackson said he would stay out as long as he felt safe — and business was good.
"I do this mainly to make a few extra bucks, so I'm not going to stay if I started feeling (the heat)," he said.
The Weather Channel's Alex Wallace reports.
Jackson said his teenage daughter stopped by to bring him a cooler with several bottles of water, and he had a couple of ham and cheese sandwiches with him.
"I'm tempted to leave them out in the sun for a while and see if I end up with grilled cheese," he joked.
If Americans ventured outside to do anything, they did it early. But even then, the heat was stifling.
"It was baking on the 18th green," said golfer Zeb Rogerson, who teed off at 6 a.m. at an Alexandria, Va., golf course but was sweltering by the end of his round.
In South Bend, Ind., serious kayakers took to the East Race Waterway, a 1,900-foot-long manmade whitewater course near downtown.
"A lot of times I'll roll over just to cool off," said Robert Henry of Carmel, just north of Indianapolis. "The biggest challenge is walking coming back up carrying a kayak three-eighths of a mile in this heat."
In Manhattan, customers who stepped in to see "Jiro Dreams of Sushi" at an IFC movie theater were there for more than entertainment.
"Of course we came to cool off!" said John Villanova, a writer who was on his second sweaty T-shirt of the day and expecting to change again by evening.
He said that earlier, he rode a Manhattan subway back and forth for a half an hour, with no destination in mind "because it really keeps you cool."
In Chicago, street magician Jeremy Pitt-Payne said he has been working throughout the three-day stretch of triple-digit temperatures, but acknowledged that he might doff the Union Jack leather vest by the end of the day, even though it's part of his British magician character along with the black top hat.
His trick for beating the heat? He starts his shows at 2 p.m., "when the Trump Tower is gracious enough to block out the sun" along his stretch of sidewalk.
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