Olympics

You can easily trigger a large storm slab on Monday within 6-8" of fresh storm snow or at one of the multiple recent interfaces. Warming temperatures may bring a deep and mostly unconsolidated upper snowpack close to a breaking point and also trigger Wet Loose avalanches below treeline early in the day.  Avoid all slopes steeper than 35 degrees.

Unrelenting weather continues with another round of snow (6-8" expected) and warming bringing the most dangerous avalanche conditions Monday morning. Natural storm slab avalanches are possible early in the day and human-triggered slab avalanches are likely throughout the day. This continues an ongoing storm and avalanche cycle that with avalanche activity observed most days since last Thursday. Widespread 8" storm slab avalanches were triggered naturally during the storm Saturday night. Propagation was extensive. At upper elevations, the 28.5" of snow that fell in the last 48 hours was low-density and non-cohesive. Recent layers are slightly denser than older snow that fell Friday night and Saturday but were not particularly slabby so most of the activity was Loose Dry. That could change as we head into Monday.

Prepare for more reactive conditions Monday if this storm delivers 0.75" of snow water equivalent in conjunction with warming early Monday. The snow from the last 48 hours needs time to settle, but instead, we're adding cohesion and weight to the slab. Watch for cracking, settlement, and heavier over less dense snow layers to confirm the avalanche problem in your area. Utilize small test slopes to check for instability. Check for firmer over less firm snow layering. Watch for signs of recent wind-loading, wind-lips, etc that may indicate larger and more reactive slabs in your area. Avoid slopes steeper than 35 degrees at all elevations until conditions have time to stabilize more. The most dangerous time periods will be when you experience heavier snow, wind loading, and warming and these ingredients are all likely to come together during the early morning hours. As temperatures cool and snowfall relents from mid-morning into the afternoon, avalanche conditions may begin to gradually improve and you can begin to ease into supported open slopes.

Keep in mind that a thin layer of surface hoar was believed to be the culprit in a large human-triggered avalanche on New Year's Eve (see photo below).  Luckily no one was caught in the slide.  The slab avalanche may have failed on weak snow grains (3-4 mm surface hoar) and was buried 12/29. This layer could be around 40" below the surface and any avalanches on the layer would be very large. We have no recent information regarding whether the surface hoar is healing, so it's advisable not to venture into terrain connected to large avalanche slopes. Below this layer, the mid and lower snowpack is strong with a series of crusts from earlier in the winter.  

There is some uncertainty in the weather forecast for Monday, in particular regarding the timing and strength of the warming. If the rain/snow line rises early Monday and you experience rain on snow, expect natural loose wet avalanches on all slopes steeper than 35 degrees and these could be large.

Deep snow immersion, suffocation, and tree wells may be an issue on Monday. Travel with and maintain visual and audible contact with your partner while in forested terrain.

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.