PENDLETON, Ore. — A Winter Storm Watch is in effect beginning late Tuesday and continuing through Wednesday for the upper east slopes of the Washington Cascades, as an atmospheric river combines with colder air to bring potentially significant snowfall to the region, the National Weather Service said.
Forecasters said snow could begin developing Tuesday evening and persist through Wednesday night, with snow accumulations of up to 10 inches possible, particularly near higher elevations, peaks and mountain crests. Snowfall totals could vary depending on elevation and how quickly colder air settles into the region.
The storm is expected to impact Snoqualmie Pass and other Cascade mountain routes, where locally moderate to heavy snow may lead to difficult and hazardous travel conditions. The Weather Service rated the system a moderate risk (3 out of 5), signaling the potential for impactful winter weather.
Officials warned that periods of heavy snow could reduce visibility and make road surfaces slick, especially during the heaviest bursts Tuesday night into Wednesday. Travelers heading across the Cascades are urged to check the latest road and weather conditions before departing and to allow extra travel time.
The Washington State Department of Transportation recommends drivers carry chains or approved traction tires, follow posted chain requirements and maintain extra distance between vehicles. Sudden changes in conditions are common during mountain storms, and delays or temporary closures are possible.
The winter storm watch means conditions are favorable for significant winter weather but details such as exact snowfall totals and timing remain uncertain. Forecasters said the watch could be upgraded to a winter storm warning if confidence increases.
Residents and travelers are encouraged to monitor forecasts closely as the storm approaches and prepare for rapidly changing conditions across the Cascade passes during the middle of the week.
