Colorado Avalanche Information Center

Cooker day in Blue Canyon. Two Wet Slab avalanches hit Hwy 50 at the west end of canyon. Cliffs were dripping and lots of active Loose Wet activity during profile. Profile was done in a shady spot to see if suspect weak layer was wetted in the absence of direct radiation (Maybe from rain the evening prior). The suspect layer at 65cm was dry on this NE-facing slope. Avalanches nearby were all E (not NE like profile) and in the sun. Investigation at the bed surface and in the crown of highway-hit avalanches showed layer at 65cm was wetted.

light wind loading

Pit dug in area where cross loading occurred. Localized cracking in areas where the top wind slab was < 15 cm thick.

Average crown height 60cm; Max 80cm, Min 30cm. Avalanche failed on a layer of 1mm FCsf immediately above a MFcr 89cm up from the ground. Avalanche propagated approximately 450 feet wide and ran approximately 350 vertical feet. Slope angle increased from 30 degrees at the crown to 36 degrees as the slope rolled over. Debris was measured up to 320cm deep.

Pit dug on slope representative of 80 highway path. Some DH present at bottom of pit around rocks. Possibly a thin layer of FC at 87cm interface, however hard to isolate on card.