Eastern U.S. swelters under extreme heat wave

NEW YORK — The temperature in New York City reached 100 degrees Tuesday as the eastern U.S. sweltered under an extreme heat wave.

Kennedy International Airport recorded 100 degrees Fahrenheit at midday, according to the National Weather Service.

Large swaths of the country were broiling under a heat dome, worsened by a humid atmosphere that’s circling the East.

After nearly 40 U.S. cities broke records for high temperatures Monday, the weather service expected dozens of records Tuesday when the heat dome should hit its peak.

But just as dangerous as triple-digit heat is the lack of cooling at night, driven by that humidity.

Amtrak reported delays Tuesday due to speed restrictions caused by the heat on routes through Washington, Philadelphia and New York.

Elsewhere, the heat was proving dangerous. Two 16-year-old hikers were rescued from a mountain in Jaffrey, N.H., late Monday afternoon, overcome by the heat, the New Hampshire Fish and Game Department said. They were described as being in and out of consciousness and were taken to a hospital.

The heat wave is especially threatening because it’s hitting cities like Boston, New York and Philadelphia early in the summer, when people haven’t gotten their bodies adapted to the broiling conditions, several meteorologists said. The dome of high pressure that’s parking over the eastern United States is trapping hot air from the Southwest that already made an uncomfortable stop in the Midwest.