Olympics

Stubborn slabs exist in wind-loaded terrain.  Loose avalanches may run on a crust at lower elevations or on less wind-affected slopes. Navigate away from slopes where you find rollerballs and wet surface snow if the sun makes an appearance.

Snow showers brought around an inch of accumulation to Hurricane Ridge during the day on Tuesday with perhaps several inches of accumulation across the southern half of the Olympic range. The new snow likely sits on a crust formed during mild and sunny daytime temperatures on Monday. 

The recent storm cycle favored Hurricane Ridge significantly, depositing 31.5" of snow from Thursday through Sunday. Saturday's mild mid-day temperatures may have formed a crust about a foot down extending up to near-treeline elevation bands. You are likely to find 2+ ft of settled snow above the more significant 3/4 melt-freeze crust. The 3/4 crust was thicker on sunny aspects that had gone through several melt-freeze cycles. Below the 3/4 crust, the upper snowpack becomes increasingly dense the deeper you dig.  The 2/23 crust can still be found 12-16" below the 3/4 crust.  Weak snow (facets) were observed below this crust last Thursday but avalanches on this layer seem unlikely. The mid-Jan crust layer that has been so prominent in the Cascades can still be found in the Hurricane Ridge area albeit at much shallower depths; ~4 ft below the surface.  Avalanches down to this layer have not been observed in the Hurricane Ridge area in over a month but the layer remains worth tracking as we wait to see what March has in store for us.  

NPS personnel reported a slab avalanche at 4700 ft near Switchback, triggered naturally late Sunday or Sunday night. The avalanche had a 1 ft crown, was 30 ft wide, ran 150 ft vertical, and reminds us of recent storm instabilities.

Storm instabilities should healing, but are most likely to linger on wind-loaded terrain on colder, shaded aspects. Wind drifts may now be covered by lower-density snow. Make use of recent sharp and pointy wind drifts to guide you away from the slopes below.  You may still trigger a stubborn large slab avalanche several feet deep. Rollovers steeper than 35 degrees will be your most likely trigger points. Cornices may not be large, but they may not be well supported. They are more likely to fail during periods of sunshine and could trigger an avalanche on the slopes below.

In less wind-affected areas, southerly aspects, and at lower elevations, you might trigger a dry loose avalanche which will be most dangerous where it can push you over a cliff or into rocks and trees. These may run farther in areas where dry snow sits on a crust.

Sunshine in the forecast for Tuesday morning could rapidly destabilize fresh snow. This problem is more likely in the southern and eastern Olympics where you may find 3-4" of fresh snow. Continue to be aware of the slopes under your feet and over your head if the sun makes an appearance. Wet or sticky snow that you sink into up to your ankle and active rollerball activity remind you to adjust your aspect away from the strong March sun.

The snowpack is quite deep and healthy for this time of year, 130% of normal as of March 1st. 

Make sure to check out the Conditions blog for more info about the very large avalanches that have released throughout the central and southern Cascades over the past two weeks.  There are some impressive photos of a few of these monster slides included in the media reel below.  

2020-21 Forecast Schedule: Avalanche danger ratings will be issued for the Olympics every Friday through Sunday and during mid-week holidays. During the week when the Hurricane Ridge road is closed, forecast information will be updated daily to include expected conditions and relevant travel advice under the No Rating label.

During the ongoing Covid-19 pandemic, continue to follow the latest guidance from local, state, and federal health officials. Avoid unnecessary risks that could impact first responders and stress medical resources.  Wear a mask when appropriate, practice social distancing, and consider recreating closer to home.