With more snow forecast for the mountains, crews with the Washington State Department of Transportation are preparing for conditions to worsen going into the weekend.
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Crews have been working to clear the passes as snow continues to fall on and off, with that snow expected to make its way into the lowlands.
Unless you have a vehicle with all-wheel drive, as of Friday morning, chains were required on both Snoqualmie and Stevens passes, where compact snow and ice are on the highways and visibility can be poor when snowing.
WSDOT said drivers should prepare for added travel time due to poor weather conditions.
Pass travelers should also be prepared for closures for avalanche control or if multiple spinouts or crashes occur. This was the case Wednesday afternoon on Stevens Pass, when both directions of U.S. 2 had to be closed when numerous drivers lost control during bad weather.
Avalanche control work stopped both directions of traffic when it began on Stevens Pass at 6 a.m. Friday. WSDOT said the work generally takes from 30 minutes to 2 hours to complete.
>>WSDOT mountain pass reports | What to carry on winter trips
Avalanche control work on Snoqualmie Pass closed the eastbound lanes at 4 a.m., Friday but the work has been completed for now.
On Snoqualmie Pass, 2 to 4 inches of snow could fall during the day on Friday with another 3 to 5 inches Friday night. Snow will continue to fall on Saturday, with another 4 to 8 inches possible. For Sunday, as many as 3 inches may accumulate during the day with the snow tapering off Sunday night.
For Stevens Pass, a total daytime snow accumulation of 1 to 3 inches is possible Friday, with another 3 to 5 inches possible mainly after 10 p.m. On Christmas day, patchy freezing fog is forecast between 8 a.m. and 2 p.m. with 3 to 5 inches of new snow in the daytime. As much as 3 more inches of snow could fall Saturday night. On Sunday, the snow tapers off with around an inch of snow falling before 4 p.m. On Sunday night, less than a half-inch of snow is forecast.