A building heat dome over the central and western United States will drive dangerous temperatures through Monday, exposing a significant share of the population to high heat.
The deepest dome is forming over the Rockies and Plains, while heat advisories stay active for portions of southern Colorado and several Midwestern states.
Thunderstorms may develop in scattered areas but will provide minimal relief from the stifling heat.
Forecasters warn the dome's intensity will delay cool fronts and extend record-breaking conditions well into next week.
Residents are urged to drink plenty of water, limit outdoor effort during peak hours, and watch out for vulnerable neighbors as the stretch of sweltering heat grows over the nation's midsection.