Obvious signs of avalanche danger may be decreasing, but the snowpack remains capable of producing surprisingly large avalanches.
Confidence
Fair - Due to the number of field observations
Weather Forecast
Thursday: Cold and cloudy. Light flurries at most. Light winds. Friday: Light snow. Remaining cool. Winds increasing to moderate SW Saturday: Light snow. Strong SW winds. Temperatures increasing. An inversion (warmer temperatures at ridge top than in the valleys) may form.
Avalanche Summary
There was a widespread cycle of large (up to size 3) naturally and remotely-triggered avalanches last Friday/Saturday. Since then, whumpfs have reminded travelers of the lurking beast. While avalanche activity has diminished, the consequences of triggering a deep layer would be severe.
Snowpack Summary
10-20cm of recently fallen snow may have been pushed into wind slabs in exposed terrain. Below this you'll likely find a hard rain crust. In the Golden area this crust exists up to around 1600m, whereas in the south it is up to 2000m or higher. In total, last week's storm produced slabs up to 1m thick in the north of the region and around 60cm thick in the south. This slab sits on the mid-November weak layer (surface hoar, facets, and/or a crust). Below this you will likely find a 15-20cm thick layer of sugary facets, which is sitting on a solid rain crust from early November. Reports of whumpfing and remote triggering on these layers suggest a persistent weakness with the potential for large propagation and large avalanches.If you haven't already, check out the awesome conditions video at https://www.skiinggolden.com/.
Problems
Persistent Slabs
Persistent Slab avalanches are the release of a cohesive layer of snow (a slab) in the middle to upper snowpack, when the bond to an underlying persistent weak layer breaks. Persistent layers include: surface hoar, depth hoar, near-surface facets, or faceted snow. Persistent weak layers can continue to produce avalanches for days, weeks or even months, making them especially dangerous and tricky. As additional snow and wind events build a thicker slab on top of the persistent weak layer, this avalanche problem may develop into a Deep Persistent Slab.