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

An "extreme heat warning" has officially been issued for nine major U.S. cities on Monday, June 23. The National Weather Service is warning nine major U.S. cities of dangerously high temperatures beginning on Monday.

An "extremely dangerous" tornado could hit a U.S. state on Sunday evening. The National Weather Service is warning of a tornado outbreak on Sunday. Severe weather, including strong winds, heavy rain, large hail and possible tornadoes are possible across many U.S. states on Sunday. One U.S. state is ...