An "extremely dangerous heat wave" is continuing to scorch a huge area of the eastern United States June 23, affecting tens of millions of people.

From Kansas City to Boston, people across the eastern half of the country are struggling to stay cool amid a sweltering heat wave. Record high temperatures were set on Sunday in parts of Louisiana, Connecticut and Wisconsin and new highs are possible in dozens of other cities on Monday.

A potentially life-threatening heat wave enveloped the eastern third of the United States on Monday impacting nearly 160 million people, with temperatures expected to climb to 104 degrees Fahrenheit (40 degrees Celsius) in the New York metropolitan area.

An intense heat wave is about to hit the central and eastern United States, putting millions of Americans to the test. Temperatures could reach historic levels, with potentially

More than 37 million Americans are under heat advisories across the U.S., according to the National Weather Service. Here's the hardest hit areas.

An extremely dangerous heat wave is underway for the eastern half of the United States as a potent heat dome reaches its peak, bringing the hottest temperatures of the year so far – the hottest in years for some cities – and putting tens of millions at risk.

An intense and nearly historic weather pattern is cooking much of America in a dangerous heat dome this week with triple-digit heat that hasn’t been seen in some places in more than a decade