Observation: Summit

Location: Fresno 2900'

Date:

December 18, 2018 2:00pm

Observer:

A. Johnston-Bloom/ A. Moderow Professional

Route & General Observations

Standard uptrack through lower meadows to ridge. High point 2900′. Tracking crusts and monitoring weak layers in the snowpack.

Red Flags

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Obvious signs of instability

Recent Avalanches?	No
Collapsing (Whumphing)?	Yes
Cracking (Shooting cracks)?	No

Observer Comments

5 large whumpfs approaching 2900' thin snowpack at this point. 30-50 cm of snow. Facets in between crusts and at the ground.
Hand pits failing on isolation near this point as well. Wind affected snow (slab) over crusts/facets.

Weather & Snow Characteristics

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

Weather

Sky cover fluctuating between overcast and obscured.
Snowing S-1 to S1 on and off.
Calm wind
Temps in the 20Fs

Snow surface

Soft snow from road to ridge. 1" of new snow fell today.

Snowpack

1100': Small facets on the ground under a thin melt freeze crust with . 6-10" of snow on top. Crust was punchy
1300' Small facets above and below melt-freeze crust. 1-2' of snow on top. Small cracking around skis.
1700': Small facets above and below 2 different melt-freeze crusts 2' of snow on top. Hand pits failing on isolation at interface of facets and newer storm snow.
2000: Crust is decomposing. No slab, soft snow over facets. No failure in hand pits again until 2700'
2600': See Pit# 1 photo. Two pits dug. HS: 60 cm. Tests failing on facets 30 cm down over melt-freeze crust. CT 19, CT 21, CT22, CT 17, ECTP 21, ECT P19.
2700': Traveling in more wind affected snow. Hand pits failing on isolation. 1F-P hard snow over thin crust and facets.
2800': See two pit photos. Additional ECT results from same location: ECTP 23 down 60 cm on facets between crusts, ECTX.
ECT were failing on facets above a crust and on facets in between crusts.
Looked at upper CT failures under lens. Failing on storm interfaces, hardness differences. Found intact stellars 15-20 cm below surface in the two pits at 2800'

Photos & Video

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