US extreme temperature warnings covered large swaths of the United States this week as a heat dome drove record heat in Billings and Salt Lake City. Billings, Montana, hit 111F on Sunday, and Salt Lake City, Utah, reached 109F.
The National Oceanic and Atmospheric Administration said heat hazards were expected to last through next Monday. In parts of the midwest and north-east, nights have not cooled enough to break the strain.
Cara Schulte on night heat
Cara Schulte, a researcher at Climate Rights International, said the lack of night-time cooling can raise the risk of heat illnesses or cardiovascular strain for vulnerable groups, including older people. She described a heat dome as a pattern that traps heat over a region and keeps conditions hot and dry.
Officials warned the public to watch for symptoms of heat-related illnesses. Heat exhaustion can show up with profuse sweating, clammy skin and fatigue, while heatstroke can cause slurred speech, a rapid pulse and a body temperature over 103F.
Heat dome across the west
Boston has seen more 90F days than average, and the National Oceanic and Atmospheric Administration predicted California and several upper midwest states would face dangerous heat levels for the first half of this week. High temperatures were also expected to blanket areas in the south later in the week.
The same hot, dry pattern is adding pressure to wildfire response. In late June, three firefighters were killed while fighting a blaze along Colorado and Utah’s border, and this week a helicopter pilot responding to a fire in Colorado died after a crash under circumstances that remain unknown.
Fires in California and
As of Tuesday, 46 uncontained fires were still burning in states including California, Oregon, Colorado, Utah, Minnesota and Idaho. Fires this year have scorched about 3.6m acres, and Trevor Stankiewicz, also a researcher at Climate Rights International, said heatwaves like this one dry vegetation across the west and can turn it into kindling.
The immediate question for people in the hottest areas is how long the warning level stays in place after next Monday, because the current forecast only carries the hazard that far. For anyone outside the record-setting cities, the practical step is to treat the warm nights and rising daytime heat as an ongoing risk window rather than a one-day spike.
