The National Weather Service called the forecast for above-average temperatures "the first significant heat wave this season."

A heat wave is moving in, with over 100 million people from the Midwest to the Northeast on alert for life-threatening heat this weekend and into next week.

Maps show where extreme humidity and 90- or 100-degree temperatures will affect around 255 million people across the United States.

Millions and millions of Americans are being warned of "dangerous" heat in more than a dozen states as the summer 2025 season officially kicks off. In parts of the Midwest and Mid-Atlantic regions more than 42 million were under extreme heat watches the morning of June 20,

Millions of Americans are facing oppressive heat, with forecasters expecting a "heat dome" to develop over parts of the county over the weekend and through next week. The National Weather Service (NWS) warns that heat related illnesses increase significantly during extreme heat events.

Weather forecasters have warned of extreme and dangerous temperatures as a major heat wave sweeps across the central and eastern U.S. states.

Hot and humid Saturday with highs in the 90s and a head index over 100 degrees. Get the latest seven day forecast from our First Alert weather team.

Record-breaking heat indices — a combination of temperatures and humidity to determine how heat really feels to the body — are possible from Kansas City to Maine.

A large dome of high pressure is settling over the eastern half of the country, ushering in several days of sunshine, dry skies — and dangerous heat — across the Chicago area. Temperatures surged into the mid-80s on Friday,