A heat dome has settled over the D.C. area, bringing high temperatures and humidity through Friday. High heat clamped down on Tuesday across the eastern United States once again, with more than 75 million Americans between North Carolina and Maine spending the day under an extreme heat warning from the National Weather Service.

By Patrick Wingrove NEW YORK (Reuters) -Tens of millions of people in major cities across the U.S. Northeast are facing record high temperatures on Tuesday on what was expected to be the worst day of an oppressive heat wave that has spread over much of the country since late last week.

More than 160 million Americans are under the highest level of extreme heat alerts during a wave of above-average temperatures.