Observation: Public
Observation Details
Name:
Matt PrimomoObservation Date:
January 1, 2021Submitted:
January 1, 2021Zone or Region:
Stevens PassActivity:
Skiing/SnowboardingLocation:
Lanham LakeObserved Avalanches
Did you observe any avalanches?
YesAvalanche Type:
Soft SlabSize:
Size 1: Relatively harmless to peopleElevation:
Near TreelineAspect:
EComments:
Observed a handful of recent storm slabs 1ft to 2ft deep, likely in the past 24hrs on a variety of aspects and a range of elevations. These were generally in the D1-D1.5 range.Photo:
Signs of Unstable Snow
Observations
The snow surface was wetted by light rain and sleet during the day. Light winds, no blowing snow observed.
Rollerballs began running as did tree bombs by mid-day with warming temperatures. It seemed like the thin layer of sleet on the snow surface inhibited wet loose activity just as it was beginning.
Off-trail travel was difficult, with heavy wet snow on the surface, and moist to dry snow below. Lots of glopping.
Boot pen was down to the 12/21 crust, which is 50-75cm down. Ski pen is slightly less, but could still feel it from time to time while skiing down.
On an East facing slope at 5,500ft (NTL) found HS of 185cm. The 12/21 crust was down 55cm, with a 2cm thick layer of 4F rounding facets (1mm). Tests indicated propagation here: CT 12 SC, and CT 22 SC. PST 30/100 (End).
On a NNW facing slope at 5,800ft (NTL) HS was 230cm, and the 12/21 crust was down 75cm, with a 3cm thick layer of 1F+ rounding facets (.5-1mm). Tests were less consistent here on this layer, but did get one sudden collapse with a compression test.
Moving forward, this layer will only continue to be stressed as we head into this weekend's storm. I suspect we may see some slides step down to it, or very large slides run on it if the storm pans out.
Media
