A strengthening heat dome over the central and western United States will drive dangerous temperatures through Monday, exposing a substantial share of the population to high heat.
The most intense dome is taking shape over the Rockies and Plains, while heat advisories remain in effect for portions of southern Colorado and several Midwestern states.
Thunderstorms may spark up in scattered areas but will do little relief from the oppressive heat.
Forecasters warn the dome's intensity will hold off cool fronts and sustain record-breaking conditions deep into next week.
Residents are urged to stay hydrated, limit outdoor activity during peak hours, and look in on neighbors as the stretch of searing heat grows the length of the nation's interior.