Mountain Weather Forecast

Weather Synopsis

It's a stormy afternoon in the mountains as a relatively mild frontal system continues to impact the Pacific Northwest. So far, the heaviest precipitation has occurred in the North Cascades, with Mt Baker already (as of 2pm) receiving around 2.25 inches of water. While temperatures with this storm have been on the warm side, cold air east of the Cascade Crest and cool easterly flow through the mountain gaps has allowed the Passes and East Side locations to see mostly snow. As the front moves through the area early this evening, look for Pass level winds to shift westerly and with it a transition to a wintery mix or rain. Overnight, the focus of the precipitation will shift to the Central Cascades as up-slope showers and a Puget Sound Convergence Zone continue to ring out additional moisture. The exact location of the heaviest rain and snow overnight is hard to pinpoint, but weather models this afternoon are trending more toward the highway 2 corridor. 

By Wednesday morning, only a few isolated showers may linger along the west slopes of the Cascades. A building high-pressure ridge will allow the mountains to dry out and for the skies to begin to clear. While you may see low-level clouds persist in the mountain gaps, this should allow for a generally dry and cool day across the mountains. 

The ridge axis will start to move inland Wednesday night into Thursday. As it does so warmer air will start to push into the region from the SW. This will be most evident in the Olympics and near the Cascade volcanoes where temperatures should warm significantly. Cold air entrenched east of the mountains will once again set up temperature inversions in the mountain valleys and passes. This could result in some patchy fog in some locations. Expect multiple freezing levels near and east of the Cascade Crest, where trailheads could be quite a bit chillier than higher up the slopes.