Olympics

Although your risk of triggering an avalanche on Tuesday has decreased slightly, avalanches may still be large.  You can still trigger a wind-drifted slab or loose avalanche on rollovers steeper than 35 degrees. If the sun makes an appearance, navigate away from areas of sticky wet snow where wet avalanches are more likely.

Temperatures rose above freezing on Monday and when combined with sunshine likely formed a thin crust on some snow surfaces. The recent storm cycle favored Hurricane Ridge significantly. The Ridge picked up 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.

While mild temperatures may have helped to start the healing process, instabilities likely linger the longest on colder, shaded aspects and where the winds drifted the snow into deeper pillows.  You can still trigger a large slab avalanche several feet deep and these slabs may not be obvious from the snow surface. Recent cornices point toward steep slopes you want to avoid. Rollover steeper than 35 degrees will be your most likely trigger points. In less wind-affected areas, 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.

The cloud cover will make wet loose avalanches less likely. 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.