Finding freedom from the heat on July Fourth will be a challenge in eastern U.S.

Heat as oppressive as British colonial rule is bearing down on the eastern U.S. heading into the long Fourth of July weekend, prompting some communities to cancel, postpone or otherwise alter their Independence Day plans.

CONCORD, N.H. — Heat as oppressive as British colonial rule is bearing down on the eastern U.S. heading into the long Fourth of July weekend, prompting some communities to cancel, postpone or otherwise alter their Independence Day plans.

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Dangerous, record-breaking heat will continue across much of the central and eastern U.S. through Friday and will continue along the East Coast through the weekend, the National Weather Service said Thursday. Temperatures in the high 90s Fahrenheit (30 degrees Celsius) were forecast for the Northeast; Philadelphia and Boston could top 100. Humidity is expected to make it feel even hotter, all but ensuring that sweat will dampen spirits at many celebrations marking 250 years of American independence.

“Anywhere you go in southern New England, you will be dealing with dangerous heat today, tomorrow and Saturday,” said Bryce Williams, a meteorologist with the weather service.