Hard windslab on southerly aspect at Paradise Divide.

CB Avalanche Center CBAC Observations

Date of Observation: 02/12/2022
Name: Garrett Eggers

Zone: Northwest Mountains
Route Description: Went down 2nd bowl on Snodgrass, through Gothic to Scofield pass, up to paradise divide, and out Washington Gulch.

Observed avalanche activity: Yes
Avalanches: I triggered a hard wind slab around 3 PM on south facing terrain at 11,400’ as I came over Paradise Divide in the upper slate region of the northwest mountains. The north side (windward) of paradise divide was strewn with sastrugi but as I crested the saddle onto the south side (leeward) it changed to stiff wind slabs. There were a couple warning wumpfs as I traversed the ridge. I was able to walk on to the middle of a deep lens-shaped slab on low angled terrain but as I skinned towards the edge of the slab and on to slightly steeper terrain (lookers right side of the crown) the slide broke ~1-2’ below my ski and propagated ~75’. The slide ran ~200’ before slowly stopping on lower angled terrain near the road below the south side of the pass. The crown was just shy of 5’ at its thickest and tapered off in either direction. I don’t have exact slope angles but it was interesting to see the slide start on a surprisingly low slope angle (felt like less than 30) and then propagate to a steeper slope. Although this wind slab was the textbook lens-shape, it filled in a saddle and wasn’t obvious to see the shape until looking at the crown, it did however sound hollow and other warning signs were present. I was not expecting a wind slab on this aspect but the wind loading was clear to see from the sastrugi and predominant wind direction on the north side.
Weather: Sunny and low 20s
Snowpack: Still some soft in the shadiest and most sheltered places but largely affected by wind and sun elsewhere. Snowpack is relatively deep for mid-February but we need new snow.

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