February 23, 2017


South Fork Eagle River: 2 Bowls (West Harp)

Obvious signs of instability (red flags):

  • Recent natural wind slab avalanches


  • Mostly cloudy to overcast, light to moderate south wind, alpine temps in the mid to upper 20s

Surface conditions:

  • Generally ~8″ creamy powder (upside down: heavier, moister snow above lighter, drier snow)
  • Exposed terrain variable: scoured, old and hard wind slab, thin wind crust


Recent natural wind slab avalanches.  The lower, larger one (D2) is pictured.  Likely triggered early Wednesday 2/22:

2 Bowls (W Harp) snowpit: ~4000′, 204* SW aspect, 30* slope, ECTP22 sudden collapse down 80cm on basal facets and depth hoar, 100cm HS

Snowpack stratigraphy adjacent to ECT (with slightly deeper HS): 0-20cm 4F basal facets and depth hoar, 20-50cm 4F+ faceted wind slab, 50-70cm 1F faceted wind slab, 70-80cm 4F facets, 80cm P faceted melt-freeze crust, 80-95cm 4F- decomposing particles from Sunday, 95-110cm 4F+ particles from Wednesday