*Extreme heat steamed the eastern United States on Thursday, while in the Midwest, temperatures dropped by as much as 40 degrees and thunderstorms delayed flights at Chicago airports.

Boston, Philadelphia, Baltimore and the Washington, D.C., area could see 100-degree temperatures Thursday. While the temperature will not climb quite that high in New York City and northeastern New Jersey, the humidity will make it feel like it, with a heat index of up to 102 degrees, according to the National Weather Service.

Authorities blame the record-breaking heat wave for the deaths of five elderly people in Tennessee, Maryland and Wisconsin in recent days.

Schools across New Jersey closed after lunch Thursday due to the heat, sending parents scrambling to make last minute child care arrangements. A few districts, such as Montclair in Essex County, opted to stay open to accommodate working parents.

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