(CBS/AP) -- Americans in much of the country will be getting a slight break from the oppressive heat on Sunday, one day after temperatures rose to above 100 degrees from the central states to the mid-Atlantic.
Forecasters say relief is on the way. The heat wave is expected to break by late today in many parts of the country, reports Elaine Quijano.
Yet for many, the cooler temperatures won't exactly be comfortable, falling only into the 90s.
The heat has been blamed for more than 30 deaths across the country, mostly among the elderly.
A 4-month-old girl died and a 16-month-old girl was hospitalized Saturday in separate incidents in suburban Indianapolis when both were found trapped in cars during near-record 105-degree heat.
Cooler air is sweeping southward in the eastern half of the country, bringing down some temperatures by 15 or more degrees from Saturday's highs. In St. Louis, the 13-degree drop from Saturday's high still will leave residents baking in 93-degree weather - the high Saturday was a record 106.
Temperatures in Philadelphia, Washington, and Indianapolis will fall to the low 90s or upper 80s on Sunday after crossing the 100 mark on Saturday. Residents in Louisville, Ky., can expect a high of 95, one day after 105-degree temperatures.
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 in Ocean and Monmouth counties on Saturday night. By Sunday morning, Jersey Central Power & Light's website reports that more than 23,000 customers were still without electricity.
Louisville, Ky. was among the hottest spots in the country this weekend, with temperatures climbing well above 100 degrees. Triple digits spread across the Midwest, Northeast and Mid-Atlantic.
In Washington, D.C., the temperature topped one hundred by midday Saturday. The punishing heat forced tourist Errin Gordon and her daughter, Madeleine, indoors to cool off.
"Definitely her being out on the heat is hard on kids, so just going to go into the museums and [staying] out of it," Gordon said.
For others, like some residents in Charlotte, N.C., respite came in the form of donated air conditioning units. One resident called it a "godsend."
Residents from Iowa to New Jersey spent the day trying to stay cool. They dipped into the water, went to the movies and rode the subway just to be in air conditioning.
If people 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.
Officials said the heat caused highways to buckle in Illinois and Wisconsin. In Maryland, investigators said heat likely caused rails to kink and led a Metro train to partially derail in Prince George's County on Friday afternoon. No one was injured, and 55 passengers were safely evacuated.
Micah Straight, 36, brought his three daughters to dance in jets of water spurting from a "sprayground" near Philadelphia's Logan Square fountain to cool off.
"We got here early, because I don't think we'll be out this afternoon - we'll be in the air conditioning," he said. "So I wanted to get them out, get some sunshine, get tired."
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