Avalanche: Summit

Location: Fresno

Date:
Observer:
Route & General Observations

Standard route up Fresno to the ridge. It was a clear and calm day. Got to rock the sunnies suffering a mild sun burn. Had an awesome crew to share the stoke of avalanche knowledge with.

Contact, Location & General Observations
Enter your contact information and a location for this observation. Note that you can submit anonymously, however if you would like to share your name with staff, but not the public, select No for "May we include your name in your observation"
Forecaster Comments

Forecasters digging pits in this area on 2.2.21 found buried surface hoar 10-15 cm down but the deeper layer that was reactive in pits 20-50 cm down was a layer of decomposing precip particles and small facets that could be mistaken for buried surface hoar. - AJB

Avalanche Details
If this is an avalanche observation, click yes below and fill in the form as best as you can. If people were involved, please provide details.
Trigger SkierAvalanche Type Soft Slab
Aspect EastElevation 2100ft
Slope AngleunknownCrown Depth 3in
Width 10ftVertical Rununknown
Avalanche Details

Small soft slab released as skier was coming down the Fresno main face. It was relatively small and did not run very far.

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

Skies were clear all day
Temps in the negatives in the am
Winds we calm for most the day. No visible snow transport

Snow surface

Widespread surface hoar from the road to 2200' becoming larger on the way up (~4mm). Just below the surface snow was dry

Snowpack

Our class dug several pits on @ 2200-2400' E/SE aspects on 14-23 degree slopes. Here are correlations of our results:
Structure: Right side up snow until we hit the 2 crust layers ~40-50cms from ground where we had 4F results above and within the crust combo. Then subtle upside down snow hardness to the ground. Basal facet layer was thinner and moist.
Strength: Shovel Shear and CT results had some failures on a buried surface hoar layer down 15-40cm. CT results we as follows: CTV, CTX, CT25 50cm down, CT12 Q1 down 30cm.
Propagation Propensity: ECT results were ECTN26 40cm down, ECTP23 40cm down, ECTP20-27 40cm down and several ECTX's
Overall the results suggested a BSH in the upper snowpack. We did not get any shearing around or in the crust combo.