Mountain Weather Forecast

Weather Synopsis

A modest frontal system resides off the Pacific Northwest Coastline on Saturday. Generally light SSW winds displaced colder air throughout the day, particularly at mid and upper elevations. This has resulted in a more stable atmosphere with a mix of stratiform low-level and mid-level clouds creating a cloudy day on Saturday. The frontal system makes its way onshore Saturday night. Light rain and high-elevation snow showers initially focus more on the Olympics during the evening hours, spreading into the west slopes of the northern Cascades later in the evening, and then into the southern Cascades and east slopes overnight. The narrow band of steadier frontal precipitation brings a period of moderate rain and snow first to the Olympics and Mt Baker areas overnight, then the rest of the Cascades Sunday morning as snow levels rise to 6000-7000 ft ahead of a late morning cold frontal passage. Mt Baker will be favored by the flow pattern and could pick up around 1" of water equivalent through Sunday afternoon, with other areas receiving less than half an inch. Snow levels fall by 1000 ft or more as precipitation becomes showery behind the front in the afternoon. An upper low lingering offshore maintains SW flow continues across the region, so don't expect much of a wind shift except from light E to light W winds through the mountain gaps. Moderate ridgeline winds remain most of the day for the Mt Baker area, but expect mostly light winds in areas less exposed to this flow direction.

Light rain and snow showers continue Sunday evening, primarily for the west slopes of the Cascades. Light rain and snow becomes steadier overnight as the offshore low makes landfall over north-central Washington State. The steady rain and snow gradually decrease and transition to isolated showers as the low shifts east of the region by late morning on Monday. Expect around 1-4" of snow for mid and upper elevations with the upper low as snow levels drop to 3000 ft by early Monday morning, rising up to 3500-4000 ft in the afternoon.