Observation: Summit

Location: Summit Lake - Fresno

Route & General Observations

Gained the southeast ridge and skinned to 2800′.

Red Flags
Red flags are simple visual clues that are a sign of potential avalanche danger. Please record any sign of red flags below.
Obvious signs of instability
Recent Avalanches?No
Collapsing (Whumphing)?Yes
Cracking (Shooting cracks)?No
Observer Comments

We got two big collapses at 2750' in a particularly thin area (total snow depth 50-75 cm). Collapses were failing in the facets at the ground, and one of them felt like it propagated a few hundred feet.

Weather & Snow Characteristics
Please provide details to help us determine the weather and snowpack during the time this observation took place.

We had a good window of visibility once we got above the valley cloud (around 2000'), but high clouds moved in and everything went flat by about 2:00. Wind was calm, with no snow. Air temp was 10 F at 2600' at 1:30.

Snow surface

Below 2500': 2-4" dust on supportable crust made for good riding conditions.

Above 2500': 4-5" dust on settled powder. Great skiing!


Supportable crust up to 2500', with snowpack about a meter deep at 2600'. Still finding basal facets at the ground, and we got some big collapses failing in this layer at around 2750' in some areas with a thin (50-75 cm) snowpack. For now, the facets at the ground are the primary concern. Starting to see surface hoar and near-surface facets at the surface, which will be an issue with new snow.

Pit at 2,600', snow depth 100-115cm
ECTP 22 on basal facets. Facets were moist, but when the block failed the facets jumped right out and the block dropped an inch.

Some other notes from the pit:
-Starting to see some faceting above and below the new surface crust.
-Layer of buried surface hoar 30 cm off the ground was unreactive in stability tests.

Photos & Video
Please upload photos below. Maximum of 5 megabytes per image. Click here for help on resizing images. If you are having trouble uploading please email images separately to staff.