Snow is already on the ground in parts of Eastern Washington, including Spokane, but downtown streets were clear by Monday afternoon.
"A wide variety of winter weather is clearly affecting the entire state," Buehner said. "It's the strongest storm of the year, so far."
Wind speeds of more than 60 mph were reported in Eastern Washington at Pullman on Monday morning, and power company Avista reported thousands of customers without power in its large service area. Winds of more than 50 mph were reported in Spokane, and a tree fell on two homes. No injuries were reported.
Winds delayed work on the Hanford nuclear reservation in southeast Washington. A large accumulation of tumbleweeds blocked some roadways, the Tri-City Herald reported. Washington Closure Hanford canceled outdoor environmental cleanup work because of the winds.
Snow accumulations in the Oregon Cascades will total 1 to 2 feet, Weishaar said.
Four construction workers at a cellphone tower project on Steens Mountain in southeast Oregon were stranded when their snow cat became stuck in a drift Saturday. They waded through waist-deep snow to reach a heated shelter with electricity.
Harney County rescuers were turned back both Sunday and Monday by white-out conditions. The weather was expected to improve Tuesday, said Matt Fine, Harney County search and rescue coordinator.
Tim Fought in Portland and Nicholas K. Geranios in Spokane contributed to this report.