Date of Observation: 12/25/2016 – 12/26/2016
Name: Zach Guy
Aspect: North, North East, East, South East, West, North West
Elevation: 10,000-12,400 ft
Avalanches: Skier triggered a couple of harmless soft slabs each day, ~6-8″ deep on slightly wind affected below treeline slopes, various aspects. SS-AS-R1-D1-S. Lots of natural and skier triggered, shallow sluffing on various aspects. L-AS/N-R1-D1-S
One natural D2.5 persistent slab ran during the storm, on a NNW aspect ATL. Crown looked about 3 to 5 feet deep and ran on or near the ground. HS-N-R3-D2.5-O/G
Weather: 12/25. S2 most of the day. Moderate NW winds with extreme gusts and intense snow transport. Overcast. -12C in the a.m.
12/26. Overcast decreased to clear. S-1 in the a.m. Very cold temps. Calm to light winds, minimal transport.
Snowpack: Christmas storm total was about 12″-14″, right-side-up. Snow depth in a wind sheltered flat slope was 145 cm. Ski pen was knee deep below treeline and ankle deep or less above treeline, where snow surfaces were stiffened by the wind. Stayed below treeline on 12/25 and saw no signs of instability except the avalanches described above. On 12/26, stomped on a number of suspect windloaded ridges N/ATL and couldn’t get anything to budge. No signs of instability observed other than the avalanches described above and some minor cracking in spots.