Heat Wave Expected to Bring Record-Breaking Temps, Heighten Wildfire Risk to Parts of Western US

A dangerous heat wave is sweeping across parts of the Western United States this weekend, bringing record-breaking temperatures to cities from Arizona to Montana. A weather pattern called a heat dome is trapping hot air close to the ground, pushing temperatures well above normal. Forecasters are warning people to stay indoors, drink plenty of water, and watch out for wildfire dangers in the area.

The National Weather Service predicted a high of 115 degrees Fahrenheit in Las Vegas on Saturday — ten degrees above normal for this time of year. Phoenix was expected to reach 116°F, and El Centro, California, could hit a record 118°F. Even Great Falls, Montana, was forecast to reach a record 104°F, showing just how wide the heat wave's reach really is.

One of the biggest dangers of this heat wave is the warm overnight temperatures. Lows are expected to stay in the upper 80s to low 90s, which means people's bodies never get a chance to cool down. Weather service meteorologist Morgan Stessman explained the problem clearly: 'There's just no relief overnight.' That kind of constant heat can be especially dangerous for older people, young children, and anyone without air conditioning.

The August record for Las Vegas is 116°F, but the city's all-time hottest day was 120°F, set in July 2024. That same summer was the hottest on record for the city. Officials say this weekend's heat, while serious, should be short-lived — temperatures are expected to drop by Sunday or Monday.

Montana is also feeling the heat in a big way. The entire east side of the state was placed under an extreme heat warning on Saturday, according to meteorologist Jeff Kitsmiller. Great Falls was expected to top its previous record of 101°F, and Helena could match or break its own record of 102°F. Still, Kitsmiller noted that a mid-July heat wave was even more extreme, when Billings reached a remarkable 111°F on July 12. Montana temperatures are expected to fall back into the 70s by Sunday.

The heat wave is also making wildfires more dangerous across the West. Hot, dry conditions cause plants and soil to lose moisture, which means fires can start more easily and spread more quickly. Most of Montana is already under a red flag warning, meaning conditions are perfect for wildfires to ignite and grow. The U.S. Forest Service also warned of an increased wildfire risk through Sunday across most of Southern California, except along the coast.

In Nevada, the heat dome has caused afternoon humidity to drop to the single digits in many places. Very low humidity dries out trees, grass, and brush, turning them into easy fuel for fires. Kitsmiller said forecasters are 'definitely worried' about fires in Montana, where blazes are already burning and strong winds are expected this weekend.

Scientists say climate change is making heat waves like this one more common, longer, and more intense. Climate change is caused by burning coal, oil, and natural gas, which releases gases that trap heat in the atmosphere. More intense heat waves lead to worse droughts, and worse droughts lead to bigger and more destructive wildfires, creating a dangerous chain reaction.

This year's extreme heat is also being partly driven by a weather pattern called El Niño. El Niño is a natural warming of the Pacific Ocean near the equator that changes weather patterns and raises temperatures around the world. Scientists say this year's El Niño is one of the most intense since records began in 1950, and United Nations officials have already warned that it broke intensity records even in its early stages.