A heatwave pushed large parts of the western United States into dangerous temperatures on Saturday, with Las Vegas hitting 46 degrees Celsius and officials warning that the worst of the heat was still ahead. Phoenix was expected to reach 47 degrees Celsius, El Centro was forecast to hit a record 48, and Great Falls was headed toward 40, also a record.
The heat mattered because it was not confined to one city or one day. A high-pressure system trapped heat near the ground from Arizona to Montana, and the National Weather Service said the dome would last only a relatively short time even as overnight lows of 26 to 32 degrees Celsius were expected to keep conditions hazardous through Sunday. That meant little relief after sunset, when bodies would struggle to cool down and cooling centers would stay busy.
In Las Vegas, the high of 46 degrees Celsius was just 1 degree below the daily record of 47, and 10 degrees above normal for the date. The city was expected to stay dangerously hot until Sunday, when the forecast called for 45.5 degrees Celsius. In Phoenix, the Justa Center opened in the afternoon as a cooling center for older adults, and about 200 people visit there each day. One person photographed outside a cooling center, Daniel Aragonez, captured what the day felt like: people moving between air-conditioned stops and trying to wait out the worst hours.
Montana was under an extreme heat warning for its entire eastern side, while most of the state was expected to fall to around 21 degrees Celsius on Sunday after the spike. Great Falls was forecast to reach 40 degrees Celsius, above its previous record of 38, and Helena was expected to match or exceed its record of 39. Billings had already reached 44 degrees Celsius during the mid-July heat wave, one of the historic marks broken earlier this month, a reminder that this summer’s heat has been arriving in waves rather than in a single burst.
The open question is not whether the region is hot enough to be dangerous; it is how much damage the heat will do before it breaks. Authorities urged people to stay indoors and hydrate, and the fire risk rose in dry areas and places already burning. With the dome expected to be short-lived but the nights still punishing, the next day offered only partial relief, not a true end to the hazard.
