You are here

Etna Pass Area

Slope next to recent avalanche that occurred on 2/3/21
Location Name: 
Mt. Etna near recent avalanche
Region: 
Outside of the Forecast Area
Date and time of observation: 
Sat, 02/06/2021 - 12:44pm
Observation made by: 
Public
Red Flags:
Recent avalanche activity
Recent loading by new snow, wind, or rain

Location Map

96067 Mount Shasta , CA
United States
41° 23' 20.6916" N, 122° 58' 59.7648" W
See map: Google Maps
California US

Snowpack Observations

Details

With the recent avalanche incident and sadness that has come from it, I wanted to head out to the location to see if there could be something to learn from the snowpack.  My deepest condolences to friends, and family of those affected by the accident.

  • Observation Location: 10T 0501335E 4581964N
  • Elevation: 6554 FT
  • Date: 2021-02-06
  • Time: 12:44PM
  • Observer: Caleb Burns
  • Sky Conditions: Clear - CLR
  • Current Precipitation:  NO
  • Air Temperature: 40 °F
  • Surface Penetration: boot penetration (PF) = 21 in (55 cm)
  • Total Snow Depth (HS): 155 cm
  • 24-hour New Snow Depth (HN24): Unknown
  • Wind Direction: N/A
  • Wind Speed: Calm (C), 0 mi/hr 
  • Column & Block Tests:
    • 36º slope angle, N Aspect 
    • ECTX
    • CT29Q2↓64cm
    • SSE↓37cm   --    this occured on a burried SH layer that wasn't sliding under the CT or ECT, but had a planar failure in the SS test - This is my layer of most concern in the current snowpack

Photos

  • Location is W and N. not, W and S.
  • Some signs of instability were noticed on nearby slopes with similar aspects and elevation. Some crowns could be seen in similar areas, but it's unknown how recent they are.
  • Difficult to see buried SH crystals could be seen on the test and observation wall at the 37cm down depth. This was the layer that was failing easily in the shovel sheer test but wasn't sheering during the CT or ECT tests.
  • The crown from the recent slide was still visible in areas but the slope was reloading since the slide had occurred.

Weather Observations

Details

Clear skies and no wind made for an excelent time in the zone.  Temperatures warmed to the 40's and good corn snow could be found on Westerly aspects late in the day.  Northerly slopes are holding a wind packed layer that sits on top of some instabilities and those slopes are staying cold with almost no sunlight hitting them during the daytime hours.  Winds have appeared to be loading the NW - NE aspects and where the recent slide occured has nearly reloaded the entire slope again.  Good snow that is still light and dry can be found on those aspects, but with additional wind more loading is likely to occur.

Statistics

Cloud Cover: 
Clear
Blowing Snow: 
No
Precipitation: 
None
Accumulation rate: 
None
Air temperature: 
Above Freezing
Air temperature trend: 
Warming
Wind Speed: 
Calm