Avalanche

Tunnel Ridge wind station

blase reardon and Lydia WilloughyFlathead Range & Glacier NP
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Quick report

We traveled to the Tunnel Ridge wind station to troubleshoot a comms issue.

  • Conditions on the first two miles of the road are not great for sleds - patchy snow, long bare spots, icy track. A few small logs at (current) road surface. 
  • In contrast, travel conditions at mid-elevations on skis were mostly straightforward. Only real obstacles were open creeks in narrow chasms of snow. Skinning did not require ski crampons, and on shady slopes, a few inches of recent snow made for dust-on-crust skinning and fast, carvable turns. 
  • Above about 6300 feet, the old snow surface (below the recent snow) was not well frozen, though our high point was only 6750 feet. Were I to travel higher, I would be paying close attention to the thickness of this crust, and where it was not supportable, I'd be very leery of steep slopes.
  • We found some minimal drifting and scouring of the recent snow, mostly on either side of a northerly ridge. 
  • Rollerballs tossed down a very steep, southerly slope mid afternoon did not entrain more snow or fan out and produce more rollerballs.
  • We saw only a few fresh loose snow avalanches - perhaps both wet and dry. 

We did not conduct column tests or a snow profile due to time constraints. 

Lots of old crowns. The two branches of Tunnel Creek only had a few narrow trails of loose snow avalanches, along with some gradually widening glide cracks. However, the head of Paola Creek was filled with what looked like fresh debris. We couldn't make out any significant crowns. Possibly a concentration of loose snow avalanche (narrow, rocky cirque).

Weather

Air Temp
mid-40s
Cloud Cover
few
Wind Loading
none
Recent Snowfall
1-8 cm
Snow Avail For Transport
small smounts

Cold morning, clear morning. A few clouds early to mid afternoon, with high stratus approaching from the west late afternoon. Light westerly winds.

Snowpack

  • Low-elevation snow cover is patchy at best. Sunny slopes mostly melted out. The snow was refrozen where it existed (shady spots and the road surface to about 5000 feet) and supported a sled both on both morning and afternoon trips up the road.
  • Mid elevation slopes were refrozen, with the crust supportable on skis all day. Ski crampons not needed. Above about 5200 feet, 1 to 8 cm of recent snow covered the refrozen surface. This snow stayed dry on shady slopes all day. It has already begun faceting. West- to northwest-facing slopes had some bare patches of crust where sun or wind had removed the recent snow.
  • From ~6300 to our high point of 6750 feet, the crust was less reliable. It was covered with up to ~12 cm of recent snow, ranged from ~7 to ~15 cm thick, and did not seem to be completely refrozen. The snow immediately under this crust was moist in hand pits. We did not dig deeper. 

Avalanche

Size
D1.5 R1
Type
HS
Count
5
Aspect
S
Trigger
N
Elevation
6000 ft