Weathercatch: Heat records tumble across the Inland Northwest once again

For the first time this summer, temperatures spiked to triple digits in many parts of the Inland Northwest this week.

The mid-August heat wave, now in its fourth day, feels jarring after a relatively temperate June and July. The last time Spokanites experienced 100-degree weather was on Aug. 31, 2022. Not only that, but temperatures soared quickly, climbing from the mid-80s on Sunday to a record-breaking 102 degrees by Tuesday.

Ever since the heat wave arrived in Eastern Washington and North Idaho on Monday, readings have nudged near the 100-degree mark or exceeded it, with temperatures rising to 20 degrees above normal.

The National Weather Service Spokane called the late-season hot spell a “major to extreme heat risk.” Residents, pets and livestock faced the greatest danger on Tuesday, when the Inland Northwest baked in some of the highest temperatures the region has seen in a long time.

Although not as severe or prolonged as the historic heat wave that gripped the region in June 2021, this week’s event has broken multiple long-standing records.

The temperature at Spokane International Airport soared to 102 degrees on Tuesday, breaking its previous record for that date of 99 degrees set in 1901. Yakima topped out at 106 degrees, breaking its record of 101 set in 2008. Lewiston hit 109 degrees, toppling its record of 105 set way back in 1897. Records were also broken in the Tri-Cities and Omak, which also reached 109 degrees, and in Coeur d’Alene, at 103; and Pullman, at 100.

What’s causing the region’s extreme heat? A strong upper-level ridge positioned over the Pacific Northwest that’s pushing hot, compressed air toward the ground and preventing clouds and cooling weather patterns from moving in. The heat will linger through Thursday, with temperatures slightly cooler but still hovering near 100 or above.

Unfortunately, the weakening of the high-pressure system will allow winds to enter the region, elevating wildfire danger across the Inland Northwest. Windy conditions are expected to last through Friday, when temperatures finally cool down (relatively) to about 90 degrees in the Spokane area.

True relief from the heat should come on Saturday, when temperatures are forecast to drop to the mid-80s. Then, cooler temperatures and even a small chance of rain arrive on Sunday.

Nic Loyd is a meteorologist in Washington state. Linda Weiford is a writer in Moscow, Idaho, who’s also a weather geek.