Avalanche

East of WMR

blase reardonWhitefish Range
View on map
Observation photo 1Observation photo 2

Quick report

Day off wander east of WMR.

  • Between crusts, moist snow, and debris from trees, riding conditions were highly variable and often grabby. Best riding was on lower-angled and shaded slopes. 
  • The 12/7 persistent weak layer was surprisingly hard to identify in a profile on a north-facing, mid elevation slope.
  • Column tests on that layer released with hard force. No propagation in the northerly profile; sudden collapse on west. 
  • The 12/18 interface was evident in two profiles and failed with moderate force. 
  • A thin rain crust caps northerly facing slopes below about 5300 feet.
  • 2 cm thick melt-freeze crusts exist on slopes exposed to the sun. On steep slopes, they're supportable. 
  • Another party rode steep, northerly terrain directly off the ridge with no incident.

The layer of surface hoar and facets buried 12/7remains a lingering concern and continues to dictate my terrain choices. 

None.

Weather

Cloud Cover
overcast
Wind Loading
none
Snow Avail For Transport
small smounts

Increasing clouds, from mostly sunny to overcast. Calm. Warm - water dripping from tree branches above 6000 ft.

Snowpack

Highly variable snow surfaces. Melt-freeze crusts, dust-on-crust, moist snow, re-frozen debris from trees, and dense settled snow on northerly slopes. HS 140-150 cm at mid elevations. 

2 quick test profiles, one at 6300 feet on a west aspect and the other at 6200 feet on a northerly aspect.

  • 12/18 interface: 20-25 cm below surface. CTM 12 or 13; ECTN  12 on N. 
  • 12/7 persistent weak layer: 50-55 cm below surface. CTH 22 on W; ECTN 28 on N. 

Did not test Nov. AR layer. 

Avalanche

Saw the slides reported in other observation from Canyon Creek this same day.