Heat Wave Expected to Roast Northern Rockies This Weekend

U.S.|The West’s fourth major heat wave will roast the northern Rockies.

• July 15, 2021, 4:45 p.m. ET

Another weekend is set to bring another string of potentially record-breaking high temperatures to another part of the Western United States.

This time, it is the northern Rockies and the High Plains, including parts of Montana, Idaho, Wyoming and Utah, that will be under a high-pressure system known as a heat dome, according to forecasts. That will set temperatures in those states soaring through the weekend and early next week, peaking on Monday.

Bozeman, Mont., could record its hottest temperature reading ever by reaching 107 degrees, according to the private forecasting service AccuWeather. Boise, Idaho, and Salt Lake City may see rare triple-digit highs on Sunday and Monday.

This will be the fourth major heat wave to afflict parts of the West since early June, bringing dangerously hot temperatures and helping fuel the deepening drought and exploding wildfires across the region.

A spate of triple-digit temperatures that roasted the Pacific Northwest in late June and early July — also the result of a heat dome — killed hundreds of people in Oregon, Washington and British Columbia. The event would have been all but impossible without climate change, according to a team of researchers.

This past weekend, California’s Death Valley hit a 130-degree high, matching a reading from last year that may be the highest reliably recorded temperature on earth. Las Vegas tied its record high, 117 degrees, and Grand Junction, Colo., topped its previous record, hitting 107 degrees.

At least 67 weather stations from Washington State through New Mexico have recorded their hottest temperatures ever this summer, the National Weather Service said this week. Those records stretched back at least 75 years.