Portland, Oregon – A colder late-winter pattern is expected to take shape across Oregon heading into early March, increasing the probability of below-average temperatures and a greater opportunity for snow during the Feb. 28 through Mar. 13 timeframe.
According to the National Weather Service Climate Prediction Center, much of Oregon carries a 40% to 50% probability of below-normal temperatures in the Week 3-4 outlook. The colder signal spans the Interstate 5 corridor from Eugene through Portland, extends east along Interstate 84 through the Columbia River Gorge, and reaches into central Oregon near Bend and Redmond.
This extended-range guidance favors a deeper trough settling over the Pacific Northwest, allowing cooler air masses to dominate more frequently compared to late-February averages. That setup increases the likelihood of lower snow levels, particularly across the Cascades and along the I-84 corridor through the Gorge.
Precipitation probabilities lean near to slightly above normal across portions of the state. When combined with colder air, that raises the potential for accumulating snow in the Cascades, Siskiyous and Blue Mountains, along with an elevated chance of measurable snowfall in some valley locations during stronger systems.
Communities from Portland and Salem to Bend, Medford and Pendleton fall within this colder signal. The Week 3-4 outlook reflects large-scale atmospheric trends rather than specific storm timing.
Additional refinements are expected as the late-February to mid-March window approaches and shorter-range guidance provides greater clarity on individual systems.
