The first round in this series of storms is expected to bring 1-2 inches of snow to the Seattle area and portions of the Washington I-5 corridor before tapering to flurries on Friday afternoon. Across the Portland area, precipitation will begin as rain on Thursday, eventually changing to sleet and freezing rain as cold air moves in. A changeover to snow is expected by Thursday night across northern Oregon.
The second storm will arrive later on Friday into Friday night with heavy snow expected for the Seattle area and the Cascade Mountains of Washington and Oregon through Saturday. Several inches of accumulation are expected during that time from around Portland up the I-5 corridor into Seattle. Some sleet and freezing rain could mix with snow again on Friday afternoon into night in and around Portland. Heavy snow is expected to spread into portions of eastern Oregon and central and southern Idaho Friday night into Saturday.
A third round of moisture is expected to arrive on Sunday, however snow from this storm will be mainly confined to the mountains and higher elevations of the Pacific Northwest.
The heaviest freezing rain will occur across southwest suburbs of the Portland metro Thursday through Saturday with localized areas seeing 0.5-1 inch of accumulation. Portland proper is expected to see a wintry mix for the majority of this event with up to 0.5 inch of ice and 6 inches of snow/sleet.
Disruptions to logistical operations are expected, including power outages within the heaviest icing area, travel delays and closures to businesses.
Winter events such as this one, with the potential for changing precipitation type over a timeframe as well as varying with elevation, require detailed forecasts. AccuWeather For Business has trained and knowledgeable meteorologists who are able to provide in-depth briefings at any time of day or night. Our site and threshold-specific warnings, as well as region-focused graphical forecasts, set your business up to handle any type of weather, keeping employees safe and minimizing disruption.
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