Avalanche Forecast

Generally light rain and snow should glance the north Cascades and Olympics Tuesday.  New loading and wind transport is not expected to play a role in the avalanche danger Tuesday.  

A modest warming Tuesday afternoon should lead to minor loose wet concerns on all aspects near and below treeline. Watch for loose wet concerns in the afternoon. Small point releases on steeper slopes have a fair bit of new and consolidated snow to entrain and would be the most problematic around terrain traps.  Storm slab avalanches should be unlikely given the generally good reports of bonding to the old snow surface and have been removed as a primary concern. 

Generally soft wind slab at higher elevations may still be sensitive, and we advise the most caution when traveling at higher and more open avalanche terrain that may be wind loaded and where colder temperatures should preserve lingering instabilities.  Watch for cracking in the snow surface and for signs of obvious wind transport such as scoured lee ridges. Be aware that locally the soft wind slab concern may extend into the near treeline zone. 

A stalled and moist frontal boundary draped over mainly the north WA Cascades Saturday afternoon finally sagged south on Sunday, with rain changing to snow generally in a north to south fashion across the PNW mountains.  A favorable temperature trend occurred with this storm, with gradual cooling from Saturday night through Sunday night.  From Saturday night through Monday morning Hurricane Ridge telemetry and NPS reports indicate about 18 inches of snow fell. Generally light showers at cool snow levels were seen through the day Monday, but moderate NW winds aloft likely transported snow Sunday night and continued into Monday. 

Over the weekend NWAC observer Katy Reid reported a generally well consolidated lower snowpack NTL with moist snow from last week's periods of rain and warm temperatures reaching down into upper and mid snowpack.  Katy also reported new wind slab developing on lee easterly aspects near treeline Sunday afternoon, although no new avalanches were reported with this concern. A NPS park ranger at Hurricane Ridge reported a backcountry skier on Sunrise Ridge above the road Sunday afternoon was able to ski cut and release a storm slab about 15-20 ft wide that covered the uphill lane with debris. Fortunately the skier was not caught in the slide due to daytime warming creating unstable slab conditions.