Portland, Oregon – Travel across the central Oregon Cascades will turn hazardous by 4 a.m. Wednesday as heavy wet snow piles up on key mountain passes through early Thursday.
According to the National Weather Service in Portland, a Winter Weather Advisory remains in effect from 4 a.m. Wednesday until 4 a.m. Thursday for the Cascades of Lane, Marion and Linn counties. Total snow accumulations of 6 to 11 inches are expected, with the highest totals centered on Willamette Pass and portions of the Lane County Cascades.
Forecasters say snowfall rates may peak between 4 a.m. and 4 p.m. Wednesday, creating slick conditions on Highways 58, 20 and 22 near Willamette Pass, Santiam Pass, Santiam Junction and McKenzie Pass. There is a 50 to 60 percent chance that Willamette Pass exceeds 12 inches during this window, while Santiam Pass carries about a 30 percent chance of topping a foot.
Snow will shift to a more showery pattern Wednesday afternoon, leading to uneven accumulation but continued travel impacts. Bridges and overpasses will freeze first as temperatures hover near the snow level.
Drivers should carry chains, pack winter emergency kits and check TripCheck.com or call 511 before departure. Conditions improve after 4 a.m. Thursday, though scattered snow showers may linger at higher elevations.
