Avalanche Forecast

Greatly decreasing winds and showers with cooler temperatures should be seen on Saturday. But don't let your guard down on Saturday.

New wind slab may be found on various aspects above treeline due to the recent and latest strong and shifting winds. This avalanche problem may also creep down into the near treeline.

Loose wet avalanches at lower elevations may remain active on Saturday. Watch for wet surface snow deeper than a few inches, pinwheels and initial natural releases that indicate an increasing loose wet avalanche danger. Be wary of steep slopes with terrain traps such as cliffs or if heavily treed, where even a small loose wet avalanche could have big consequences.

Recent cornices are very large and have likely been weakened during this most recent storm cycle. Natural cornice releases and resulting slab avalanches are dangerous and unpredictable. Give cornices a wide berth if traveling along ridge-lines and avoid slopes below large cornices. See a blog post regarding cornices here.

Other avalanche problems not listed that may be encountered on Saturday include:

Storm slab in more sheltered areas above treeline that experienced rapidly accumulating snowfall for more than a few hours.

Remember that solar effects can rapidly increase the touchiness of various type of avalanches at this time of year.

Weather and Snowpack

March was a wet and wild month for weather and avalanches in the Cascades. The last widespread avalanche cycle during this stretch occurred March 28th-29th.

Fair but cool weather was seen in the Cascades Monday and Tuesday. Reports generally indicated strong surface or near surface crust layers and shallow recent snow. 

A stalled frontal boundary on Wednesday to Thursday morning brought heavy rain and snow to Mt Baker with light rain or snow for the rest of the Cascade west slopes. Snow levels were generally between 4500-5000 feet in the northwest Cascades and 5000-6000 feet in the central-west and southwest Cascades. For the 3 days ending Friday morning NWAC stations along the Cascade west slopes had about 1-1.5 inches of WE except with about 3.4 inches of WE at Mt Baker. This WE will have fallen as snow above the snow levels.

A deep low pressure system moved north just off the Washington coast on Friday. SSE flow aloft Friday morning will shift to the SW by Friday night with the most rain or snow continuing on the volcanoes. Snow levels are running in the 4-5000 foot range on Friday. By Saturday morning 24 hour WE at NWAC stations along the Cascade west slopes should get another .5-1 inches of WE except for about another 2 inches of WE at Mt Baker! Once again this will have fallen as snow above the rather low snow levels.

Recent Observations

North

NWAC pro-observer Lee Lazzara was at Little Devil Peak in North Cascades on Monday 4/3. Near and above treeline Lee found about 4 inches of recent storm snow over the most recent crust, and wind slabs averaging about 1 foot on N-E aspects below ridges. Snowpack tests indicated triggering of wind slabs to be stubborn. There was evidence of recent large cornice failures. The recent strong rain crust dominated the snowpack below treeline with shallow wet snow conditions during the afternoon. Shallow cold snow was preserved on steep shaded terrain near and above treeline.

The Mt. Baker pro-patrol reported easily ski triggered loose wet avalanches Thursday morning peeling off the most recent 4-6" inches above 4500 ft and running well. Below 4000 feet, the random snow pillow collapse would trigger natural loose wet avalanches due to above freezing temperatures and continuing rain. 

Central

The Alpental pro-patrol in a pit on the upper mountain reported alternating layers of stable crusts and wet snow in the upper snow pack on Friday. At the base they found gradually increasing density with depth of large wet grains of wet snow.

A report via the NWAC Observations page for Friday indicated easily triggered loose wet avalanches on Tonga Ridge west of Stevens Pass on Friday.

South

No recent observations.