The stifling heat wave that blanketed most of the country for the past week days relented on Saturday as storms swept through the Midwest and Northeast.
Meteorologists said an advancing cold front managed to bring temperatures down a tad in some portions of the Great Lakes region on Friday before making a drive through the Northeast.
The cold front reached the Ohio Valley and parts of the Northeast on Saturday and was expected to hit the mid-Atlantic States on Sunday, the Weather Channel reports.
The front brought stormy conditions with it. A tornado with 110-mph winds collapsed the wall of the athletic center at Ursuline College in northeast Ohio early Saturday and damaged other buildings but there were no injuries, The Associated Press.
In Philadelphia, the threat of lightning and heavy rain forced people attending a Taylor Swift concert to flee their seats and move into a concourse area until the storm swept through, NBCPhiladelphia.com reported. Concertgoers were allowed to go back to their seats at 10:30 p.m. ET. The storm also causes scattered power failures.
Over the weekend, temperatures in Chicago were expected to drop more than 15 degrees, driving the heat down from 94 on Friday to an anticipated 78 degrees on Sunday.
In the Northeast, the week-long heat wave peaked at 10 degrees higher than July temperatures in past years. On Friday, the heat broke daily record highs in Burlington, Vermont, Portland, Maine and Boston, where temperatures reached 99 degrees with a heat index of 105.
The hot and humid conditions have driven many people indoors, causing record-breaking power usage in New York City on Friday, as temperatures in some locations hit 100 degrees. Saturday was the seventh straight day with temperatures in New York at 90 or above, the longest heat wave in the city since 2002, NBCNewYork.com said.
The heat is the suspected cause of at least 13 deaths nationwide, three of which occurred in Milwaukee. The National Weather Service says Milwaukee recorded four consecutive days of highs in the mid-90s, with the heat index reaching over 100 degrees. But on Saturday, the city saw highs only in the low 80s.
Thirty-five people were treated for heat-related illnesses on Saturday at a rally for Trayvon Martin in Dallas, Texas, but no one was taken to a hospital, according to city Fire Rescue spokesman Jason Evans.
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