A powerful heat dome building across the western and northern United States is threatening all-time temperature records this weekend, as millions face extreme heat, worsening drought conditions, and an elevated wildfire risk following an earlier heat event in the Midwest and East.
Western Heat Dome Targets All-Time Records
A developing weather pattern is bringing the potential for historical high temperatures to several western and northern locations. AccuWeather forecasters report that millions of people across the West could see temperatures soar well above normal by Sunday, with some areas approaching or surpassing their hottest temperatures ever recorded.
This new high-pressure system arrives on the heels of another widespread heat event that baked the Midwest, South, and East leading up to the Fourth of July holiday. That earlier heat dome brought triple-digit temperatures to cities from the Plains to the Northeast, affecting more than 200 million people at its peak.
While both events share the same underlying mechanism of a strong upper-level high-pressure system trapping hot air near the surface, the newest system concentrates its most intense heat farther west. Scorching conditions are stretching from Utah and Idaho through eastern Montana, the Dakotas, and into parts of Minnesota before eventually shifting east later in the week.
Specific Temperature Projections and Threatened Records
Forecasters point to several cities where existing temperature records face an immediate challenge. In Billings, Montana, temperatures are forecast to reach 109 degrees Fahrenheit on Sunday, which would break the city’s previous record of 107 set in 2002.
Salt Lake City is also tracking near its all-time high of 107 degrees, with expected weekend highs of up to 106 degrees. Additional locations facing extreme heat include Grand Junction, Colorado, where temperatures could climb to 105 degrees—nearing its 2023 record of 107—and Casper, Wyoming, where highs may reach 104 degrees to tie its all-time high.
Further south, interior California is also bracing for severe heat. National Weather Service forecasters warn that temperatures away from the coast will range from 90 to 105 degrees by Wednesday, with Woodland Hills in the San Fernando Valley expected to hit 110 degrees.
Drought Expansion and Intensifying Wildfire Dangers
Beyond immediate health concerns, meteorologists warn that the persistent heat will rapidly dry out vegetation and exacerbate existing environmental hazards.
AccuWeather expert meteorologist Paul Pastelok noted in an email that the region will dry out quickly, intensifying fire danger and expanding drought conditions to merge with severe weather already gripping western Nebraska, western Kansas, and northeast Colorado.
The threat is compounded by incoming monsoonal moisture. While expected to bring thunderstorms to parts of Arizona, New Mexico, Utah, and Colorado, some of these storms may produce little rainfall. These dry thunderstorms carry a high risk of igniting new wildfires when lightning strikes parched land.
Watches, Warnings, and What Comes Next
National Weather Service offices have issued extensive advisories across multiple states. Extreme heat watches are active for Wyoming, Montana, North Dakota and South Dakota, while extreme heat warnings cover California, Arizona, Colorado, and Utah. Less severe heat advisories stretch into Nevada, Idaho, and New Mexico.
The intense heat will not remain isolated in the West indefinitely. Forecasters indicate that the heat dome will shift eastward during the second half of next week, potentially returning dangerous heat and humidity to the Mid-Atlantic and Northeast.
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