| Trigger | Natural | Remote Trigger | No |
| Avalanche Type | Hard Slab | Aspect | East |
| Elevation | 3400ft | Slope Angle | unknown |
| Crown Depth | 2ft | Width | 2500ft |
| Vertical Run | 2000ft |
Avalanche: Summit
Location: Fresno
Toured up Fresno to try to get to a crown from a large natural avalanche. We stopped shy of the crown after getting some large collapses on a very weak snowpack, and no good way to cross some big terrain. We dug a pit at 2800′ and found a wet snowpack with a very weak layer of large facets buried about 10″ deep. We saw other natural activity on Twin Peaks and across Colorado Creek.
Avalanche Details
Very large natural on Fresno. I measured the crown width on Google Earth and best estimate is around 2800' wide, 2000' vertical run. Based on our snowpits and multiple hand pits on the way up, the avalanche most likely failed on a layer of advanced facets buried around 2' deep, possibly deeper in some parts of the start zone. The avalanche stepped down to large facets on the ground, leaving large areas totally wiped out down to dirt and rocks. Most likely triggered during strong winds yesterday (12/26).
We saw a large slab avalanche on Twin Peaks (see attached photo) on our drive down, which looked to have been triggered by a small wet loose avalanche. We saw one more fresh slab avalanche across Fresno Creek off of Colorado (photo attached), which was a few hundred feet wide and ran maybe 500' vertical.
Obvious signs of instability
| Recent Avalanches? | Yes |
| Collapsing (Whumphing)? | Yes |
| Cracking (Shooting cracks)? | No |
Observer Comments
Collapsing, fresh very large avalanches, and a lot of liquid water in the snowpack. Scary out there today.
Weather
23 F in the parking lot when we started skinning, 36 F when we got back to the truck. Noticeably warmer as we gained elevation. Mostly cloudy skies with light westerly winds.
Snow surface
Variable. Areas with old wind slabs were locked up and supportable, areas without old slabs were loose and sloppy. Moisture in the snow for the upper 6-18" of the snowpack, varying largely depending on how firm the snow at the surface was.
Snowpack
See attached snowpit profile.
Large natural avalanche on Fresno, likely occurred during yesterday's strong winds. 12.27.2021
View of the left flank of the Fresno slide. 12.27.2021
Natural avalanche on Twin Peaks. This one looks like it was triggered by a small wet loose avalanche that released just above the deepest part of the crown tucked up in the rocks just to the left of the center of the frame. 12.27.2021
Natural slab off Colorado, a little ways up Fresno Creek. 12.27.2021
Stout crust on the surface at about 2600'. The surfaces were variable, and 100' away from this crust we were sinking up to our ankles in moist facets with our skis on. 12.27.2027
Snowpit profile from 2800'. This would be about 600' below the start zone of the large natural avalanche. 12.27.2021