Since records exist, Spokane just ended the driest summer

Spokane just experienced its driest summer in recorded history.

From June 1 through Aug. 31, a mere 0.26 inches of rain fell at Spokane International Airport, compared to the average summertime rainfall of 2.33 inches, considering all summers since 1881. This resulted in a substantial seasonal rainfall deficit of 2.07 inches, according to National Weather Service data.

Summer 2025 beat the previous record low of 0.44 inches set in 2015, and before then, 0.48 inches set in 1949.

Weather records for Spokane date back to 1881, so this new record-breaking dryness covers a span of 144 years.

Spokane received less rain than the same period last year, when summer 2024 became the city’s third-hottest summer recorded. During that intensely hot duration, 1.12 inches of rain fell at the city’s airport. While considerably lower than the average rainfall amount, it’s still a soak compared to this summer’s scant 0.26 inches.

The lack of rain was fairly widespread throughout the Inland Northwest. Pullman also notched its driest summer on record with only 0.51 inches, compared to its average amount of 2.6 inches, according to data from the Western Regional Climate Center.

To the south, Lewiston clocked its second-driest summer on record with 0.44 inches of rainfall, compared to its average of 2.5 inches. That city’s No. 1 driest summer occurred in 1973, with a total of 0.27 inches. Considering Lewiston’s semi-arid climate, it’s interesting to note that Spokane saw even less rain this summer.

Meanwhile, Wenatchee picked up 0.18 inches compared to its 1.07 summertime average.

Overall, most of the Inland Northwest experienced only a few small rain events. Why was it so dry?

Large, stagnant blocks of high pressure in the atmosphere acted like gigantic gates, preventing moisture systems from drifting our way. Prolonged heat played a role as well. Temperatures in Spokane ran 4 degrees warmer than average for summer. What’s more, the heat arrived early, reaching 94 degrees on June 9. Although the area didn’t eclipse 100 degrees during the three-month period, there were just enough 90-plus days (including 95 degrees on Aug. 31) to tip the scales toward abnormally hot.

So here we are, a few days into meteorological fall, and summer heat is raging. On Sept. 1, which fell on Labor Day this year, temperatures climbed to 99 degrees in Spokane and 102 in Lewiston. Since then, it has only gotten hotter, and the region more parched. With triple-digit temperatures extending from Wenatchee and Yakima to Spokane, Lewiston and Coeur ‘d Alene, we are now experiencing our hottest temperatures of the year.

Meanwhile, an extreme heat warning – the highest alert level issued by the National Weather Service – covers parts of central Washington, including Yakima, Wenatchee and the Tri-Cities, until Thursday at 8 p.m. Spokane and most of Eastern Washington and North Idaho remain under a heat advisory.

“Record high temperatures for September are possible for multiple locations,” the weather service in Spokane stated on its online forecast discussion. The heat will persist overnight, when even the low temperatures are expected to run well above normal, the agency added.

“Residents of the Inland NW need to take this heat seriously and avoid activities that would lead to heat related illnesses,” the weather service advised.

These hot, dry conditions are expected to linger through the workweek, with the mercury sinking only slightly to 95 on Friday. As for the weekend? Cooler but still abnormally warm and dry for early September.

It’s possible the hot, dry weather pattern will reverse course next week. Weather model data indicate that the block of high pressure anchored over our region could finally weaken and shift east, allowing a cool, wet air mass to take its place.

Should this occur, we can all welcome the return of rain.

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