Explained: Heat dome expands across the central United States, creating dangerous conditions for millions

A heat dome is expanding across the central United States, pushing temperatures above 100 degrees from Dallas to North Dakota.

heat dome

A weather pattern where atmospheric conditions trap heat, creating sustained high temperatures.

extreme heat warning

A National Weather Service alert issued for dangerously high forecast temperatures.

heat advisory

An NWS notice indicating hot weather conditions that could be hazardous if precautions aren't taken.

HVAC

Heating, ventilation, and air conditioning systems that technicians like Santos repair.

National Centers for Environmental Information

The agency that tracks and reports average U.S. temperature data.