Mammoth Crest

SNOWPACK OBSERVATION
Submission Info
Forecaster
Monday, December 25, 2017 - 12:00pm
Red Flags: 
37° 35' 7.08" N, 119° 0' 4.68" W
Snowpit Observations
More detailed information about the snowpack: 

Toured up to 10,000' under the Mammoth Crest under the Sister Chutes between Hammil Bowl and TJ Bowl. Conditions were warm and sticky, almost spring-like, with air temps hovering around 5 deg. C between 9200' and 10,000'. Snow surface temps were around 0 deg. C. Snow surfaces on N, W, and NE aspects were moistening facets and decomposing-fragmented precip particles from the 21st. SW-S-SE aspects ranged from moist facets to melt-freeze crusts. Snow depths: below 9200' is very thin and patchy; around 40cm between 9200' and 9800'; between 65 and 80cm around 10,000'. The snowpack still generally consists of sugary faceted snow throughout. The crusts and wind slabs from small storm events so far this year are still present but breaking down into faceted grains with the main differences between layers being hardness and grain size. Hand shears on W-N-E aspects between 9400' and 10,000' pulled with hard force and were mostly unconsolidated. Kick tests in wind drifts on W-N-NE aspects showed some localized (~1m long) cracking. All observed cracking was in 4F+ wind slabs on top of F hard facets 20cm down.

Other notable observations: an old D1 wind slab avalanche was observed near the top of Hammil Bowl at about 10,900' on a NW aspect. Best guess is that this released during the last wind event with snow available for transport between the 20th and 22nd. The warm temperatures creeping their way up slope have also resulted in a decent sized deformation crack opening up just above the large cornice on Jaws above Crystal Lake. Snow was moist enough to cause small rollerballs from our turns even on N aspects up to 9500' on our way down around noon. Winds were consistent but light from the W and SW all day. No blowing snow anywhere with warm temps and humidity making even the softer surface snow more difficult to transport. Obstacles are becoming more frequent and closer to the surface. Be careful out there. Pray for snow.

Weather Observations
Blowing Snow: 
Air temperature: 
Wind Speed: 
Precipitation: 
Air temperature trend: 
Wind Direction: 
Accumulation rate: 
More detailed information about the weather: 
-- placeholder --

ESAC receives significant financial support from ...