Extreme heat is impacting states across the country. See maps of high temperature forecasts and heat index levels.

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.

High temperatures across the Plains, Midwest, mid-Atlantic and Northeast are expected to hit at least 15 degrees above normal ...

Millions of Americans are under extreme heat warnings on Friday, June 20, as sweltering temperatures are expected to reach the triple digits in some areas. The National Weather Service (NWS ...

The eastern US is experiencing a severe heat wave impacting 160 million people, with temperatures hitting 104°F in New York.  ...

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

Extreme heat is impacting states across the country. See maps of high temperature forecasts and heat index levels.

Extreme heat is impacting states across the country. See maps of high temperature forecasts and heat index levels.

Extreme heat is impacting states across the country. See maps of high temperature forecasts and heat index levels.

Extreme heat is impacting states across the country. See maps of high temperature forecasts and heat index levels.