Mountain Weather Forecast

Weather Synopsis

The low pressure system that brought active weather mid-week continues to move eastward and transits southern Alberta as of Friday afternoon. In its wake, our region remains with moderate low-level onshore flow, and cold air aloft arriving on NW flow as an offshore ridge gradually expands into our region. 5000 ft temperatures are unseasonably cold, topping out in the mid-20s to low 30s across the region. There's enough low-level moisture and low-level instability beneath the incoming ridge to keep isolated snow showers and weak convergence going at times, but only a few snow flurries are even reaching the Cascade Crest or points east.

This pattern continues overnight as the ridge gradually replaces the outgoing trough. The west slopes of Mt Hood, Snoqualmie to Stevens Pass, or areas west of Mt Baker might pick up a trace of new snow as skies mostly cloudy skies gradually become partly cloudy. Further east, expect clearing skies and strong radiational cooling.

After a chilly start to the day on Friday, expect quickly rebounding temperatures topping out 10-15F warmer than Thursday thanks to a modest ridge of high pressure moving onshore bringing mostly sunny skies. Expect a few popcorn cumulus clouds to build in the afternoon, particularly for areas north of Mt Rainier. Wispy high clouds might also move in late in the day. Variable, but slightly NNW ridgeline winds at the start of the day generally switch more southerly as the day progresses.

Friday night through Saturday, a closed low positions itself well offshore, increasing southerly winds over our region. Some moderate wind gusts might be expected for the Olympics and Mt Baker areas by Saturday afternoon as freezing levels rise to 7000 to 9000 ft. High clouds thicken, particularly over western portions of the forecast region.