Mountain Weather Forecast

Weather Synopsis

A major winter storm will impact the region with major snow accumulations and significant winds over the next 24 hours. A deep upper-level low positioned at the base of the Alaska Panhandle Saturday afternoon has spawned a developing surface low tracking toward Vancouver Island. Out ahead of the low pressure, a frontal system will impact our region. A warm front currently spreads heavy precipitation into SW Washington State with lighter precipitation extending NE as far as Bellingham. This package will continue to lift northest through the evening hours, with a trailing cold front pushing SE and shifting the heaviest precipitation toward Mt Hood on Wednesday morning. With cold air in place across the region, the warm front will moderate air to the west of the Cascades enough to push Snow levels up to around 3500 ft early Wednesday for Mt. Hood. Warming won't be impactful for most of Washington's mountains. Deep, cold air east of the Cascades will be funneled through mountain gaps, potentially creating blizzard conditions in some areas before low-level flow switches westerly with the cold front early Wednesday. Snow tapers to showers in most areas by Wednesday afternoon, with a slight cooling trend as the upper low moves just offshore. As a secondary low may re-organize precipitation over southern portions of our region while northern areas could see a break in the snow late in the day. With cold temperatures and high snow ratios, we expect 1-2.5 ft of snow for most areas of the Cascades and Olympics by Wednesday evening with slightly higher amounts not out of the question for the Volcanoes.

The trough moves onshore Wednesday night and Thursday with periods of snow showers and banded precipitation associated with the surface low adding to snow totals.