Avalanche: Summit

Location: Fresno Ridge

Date:
Observer:
Route & General Observations

Toured up SE shoulder of Fresno Ridge. Observed active wind loading from strong N winds and noticed two large crowns at 1:30pm on an East aspect of Fresno Ridge. Unsure of when they occurred, but didn’t notice them while driving, but are in an area that is challenging to see from the road.

Also observed a recent glide avalanche on a South aspect of Wilsons, across the valley from Fresno.

Avalanche Details
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Trigger NaturalAvalanche Type Hard Slab
Aspect EastElevation 3600ft
Slope AngleunknownCrown Depthunknown
Width 600ftVertical Run 2000ft
Avalanche Details

Wind triggered D2 and a D3 avalanche on Fresno Ridge, based on the size of the debris and how far it ran.

Also a natural glide avalanche on a South aspect of Wilson's

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?Yes
Collapsing (Whumphing)?No
Cracking (Shooting cracks)?Yes
Observer Comments

Two large avalanches on Fresno East aspect - Debris from one the avalanche's ran surprisingly far to ~1500'.
Glide avalanche on S aspect of Wilson's
Active wind loading

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

Clear skies
Strong North ridgetop winds
Temps in the teens to low 20Fs, but felt warmer due to the sun's radiation.

Snow surface

2cm of new snow on crust at lower elevations (protected from wind)
Above 1600' - sastrugi, breakable wind crust, and pockets of 5-10cm of loose snow.
3-5cm sun crust on South aspect of steep gully - winds were keeping the surface dry at 3pm.

Snowpack

Dug a pit in a protected meadow on Fresno
~2500', East aspect, 30* slope, HS=120cm
CT15 failed 80cm below the surface on 2-3mm facets, ECTX
CT3 on 6mm BSH down 25cm below the surface
Overall poor structure, 4 lemons on the January facet layer, boot pen= waist deep in protected meadow

Photos & Video
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