Heat wave expected to bring record-breaking temps, heighten wildfire risk to parts of Western U.S.

A ridge of high pressure is holding heat close to the ground — what's known as a heat dome — from Arizona to Montana, though the good news is that it will be relatively short-lived, National Weather Service meteorologists said. A dangerous heat wave will bring record-breaking temperatures to parts of the Western U.S. this weekend, prompting warnings for people to stay inside and heightening wildfire risks in areas that already are dry or burning.A ridge of high pressure is holding heat close to the ground — what’s known as a heat dome — from Arizona to Montana, though the good news is that it will be relatively short-lived, National Weather Service meteorologists said.The National Weather Service on Saturday forecast a high of 115 degrees Fahrenheit (46 degrees Celsius) in Las Vegas, the hottest temperature of the year.

Phoenix is expected to reach 116F (47C), while El Centro, California, was expected to hit a record 118F (48C). Even parts of Montana were expected to broil, with a record 104F (40C) forecast for Great Falls.In Las Vegas, Saturday's forecast high was 10 degrees above normal, with meteorologists warning of dangerous heat through Sunday, when the high is expected to be 114, said weather service meteorologist Morgan Stessman.Overnight lows in the upper 80s to low 90s will make the situation especially dangerous because it doesn't allow people’s bodies to recover. “There's just no relief overnight,” Stessman said.People are urged to stay indoors and hydrated.The August record for Las Vegas is 116F (47C), while the hottest on record was 120F (49C) in July 2024, which also was the hottest summer on record, Stessman said.In Montana, the entire east side of the state was under an extreme heat warning Saturday, said weather service meteorologist Jeff Kitsmiller.Great Falls was expected to reach 104F (40C), topping its previous record of 101F (38C), while Helena was expected to match or surpass its record of 102F (39C), he said.Still, it’s not as bad as the heat wave in mid-July, when some areas broke all-time records, including Billings, which reached 111F (44C) on July 12, Kitsmiller said.“That was a rare heat wave,” he said.

“This one fits for this time of year.”By Sunday, much of the state will have highs in the 70s, he said.Heat is exacerbating wildfire risksForecasters are warning that this heat wave, combined with drying from past heat, will add to wildfire risks across the West.“We’re definitely worried about that” in Montana, where fires already are burning and high winds are forecast for the weekend, said Kitsmiller, adding that most of the state was under a red fla… The National Weather Service on Saturday forecast a high of 115 degrees Fahrenheit (46 degrees Celsius) in Las Vegas, the hottest temperature of the year. In Las Vegas, Saturday’s forecast high was 10 degrees above normal, with meteorologists warning of dangerous heat through Sunday, when the high is expected to be 114, said weather service meteorologist Morgan Stessman.

Overnight lows in the upper 80s to low 90s will make the situation especially dangerous because it doesn’t allow people’s bodies to recover. “There’s just no relief overnight,” Stessman said. People are urged to stay indoors and hydrated.

The August record for Las Vegas is 116F (47C), while the hottest on record was 120F (49C) in July 2024, which also was the hottest summer on record, Stessman said. In Montana, the entire east side of the state was under an extreme heat warning Saturday, said weather service meteorologist Jeff Kitsmiller. Great Falls was expected to reach 104F (40C), topping its previous record of 101F (38C), while Helena was expected to match or surpass its record of 102F (39C), he said.

Still, it’s not as bad as the heat wave in mid-July, when some areas broke all-time records, including Billings, which reached 111F (44C) on July 12, Kitsmiller said. “That was a rare heat wave,” he said. Heat is exacerbating wildfire risks Forecasters are warning that this heat wave, combined with drying from past heat, will add to wildfire risks across the West.