Test slopes, Snowpack Tests, and Conditions near TJ Bowl

SNOWPACK OBSERVATION
Submission Info
Forecaster
Monday, January 8, 2018 - 2:00pm
Red Flags: 
Whumphing noises, shooting cracks, or collapsing
Recent loading by new snow, wind, or rain
37° 35' 10.68" N, 119° 0' 10.08" W
Snowpit Observations
More detailed information about the snowpack: 

Toured up low angled (>30deg), sheltered slopes towards TJ  Bowl to test new storm snow and the persistent facets buried under the rain crust that was deposited on 1/4. Snowing all day: moist, irregular flakes. Snowfall rates varied from very light to moderate (S-1 to S2) throughout the afternoon, but trended towards heavier as the day went on. Temperatures were warm: 0.5deg C at 8700' at noon with a Tsurf= 0deg C. Winds were much lighter than expected. Conditions were mostly calm with some light to moderate gusts from the W. New snow at 9032' at 1225pm was 7cm, 12cm at 9393' at 1315pm. 12cm was pretty much as deep as the new snow got up to 10,000' where we turned around. Visibility was about 1,000' all day; couldn't see the Crest at all.

Hand shears on ENE-N-NW-W slopes between 9200' and 9500' failed easily, whole block on top of the rain crust which is buried down ~25cm. Kick tests at 9200' on NE aspects produced some small (D1) storm slab avalanches sliding on the rain crust, rollerballs were also common from our skin tracks (see test slope video and pictures). Some occasional, small whumphing in flat terrain. Some ~1m long shooting cracks (see shooting crack picture).

Test snowpit at 9869' on a 14deg slope, NNE aspect showed the faceted snow buried under the rain crust to still be reactive. CT3 SP down 46cm on the facet layer, CTV same layer, ECTP 4 same layer (see shovel tapping video). Upper snowpack structure is 12cm of 4F- hard irregular and moist new snow from today on top of 13cm of the dry F hard settled precipitation particles from the storm on 1/6 on top of the P+ hard rain crust from 1/4 on top of 20cm of F hard decomposing precipitation particles also from 1/4 on top of F- hard facets. The F- hard facets and the new now on top of the rain crust were the layers of most concern in our tour today.

Snowpack photos: 
~1m long shooting cracks.
Kick Test Results on the rain crust buried on 1/6.
Several small D1 Results from Kick Tests.
Snowpit videos (tests, etc): 
Weather Observations
Blowing Snow: 
Air temperature: 
Wind Speed: 
Precipitation: 
Air temperature trend: 
Wind Direction: 
Accumulation rate: 
More detailed information about the weather: 
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