CAIC Observation Report
AvalancheCrested Butte Avalanche Center · Jan 14, 2014
Weather
snow, heavy at times, 4-10" new snow.
Snowpack
Backcountry Observations Administration You are logged in with administration privileges. Tuesday, January 14 Crested Butte Area, S-SE at 9000-11000 WEATHER OBS: Mid for us with 20f starting the trip, snowing light S1 and wind gusts, 30mph from the W moving snow around. Swirling at times and decreased to 5-10mph by 2.30 in the afternoon up high around 11,000ft.S-1 snowfall in the afternoon. SNOWPACK OBS:SW aspect at 10,500, HS 150cm. 20cm of new snow deeper on leeward aspects. multiple crusts seen within the pack, some at 1F. CT showed CTE results at the new/old snow crust interface, other results inconsistent No results from ski cutting. Crust is supportable.1 large collapse while breaking trail at 10,500ft. 1 avalanche observed R1 D1 on the S aspect of Evans basin 10,000. cornice drop the likely trigger. Ski pen 20cm, boot pen 40cm. CBMG Crested Butte Area, S at 9000-12000 Wx: Moderate winds (15 mph) and 18 degrees at TH at 5:30 AM. Little wind through the trees, then moderate to strong winds near treeline, and it felt much colder up high. Winds were strong enough to transport snow and build winddrifts in open terrain from treeline to the valley. Couldn't see into the bowl from treeline due to being in the clouds and the windy snow. Sx: Snowing very lightly. New snow of 3"-6" on the skin track. Snow was a little more dense than January "Cold Smoke." Track was firm only in very wind-exposed areas NTL. Ax: Skied glades. Snow was between 3"-6" of wind-buffed powder over a firm and unbreakable crust on southerly aspects. A stronger windcrust was developing on aspects that tilted westerly. No collapsing heard on tour. No cracking. No avalanches or instability observed, but it was difficult to see into higher terrain or across the valleys. Good times, good turns, and cold phalanges were had by all. Crested Butte Area, S-SE at 9,100-11,000 WEATHER OBS: Cold, windy, with gusts around 30-40 moving snow and swirling in the trees. Ground blizzard at times. Snowing S1 throughout day. SNOWPACK OBS: ~20cm of new snow. A buried crust felt and noticeable only where slop angle exceeded 30*. Supportive mid pack to ski pen but not boot pen. Overall depth roughly 1.2M. A few collapses noted down low in the trees while setting the up track, but none near treeline or on steeper slopes. Of note, the gully just to climbers right when starting the skin track had a well developed cornice on it when we returned in afternoon. Ski cuts very easily triggered 2 separate fresh shallow windslabs that took out the entire terrain feature and ran debris into the gully. Overall estimated at R4 D1.5 CBMG Paradise Divide Area, NE at <11,000 GFP don't show signs of instability. BUT, blustery winds even below treeline mixed with calm. Snowing all morning probably 2 inches fell while out there. Ski pen 10-12 inches. Top six inches lighter than the rest. 115 cm of snow before you hit midpack. Crested Butte Area, SSE at 9000-11000 skied Southeast facing terrain N/BTL with fresh snow and wind. Weather cool temps, Winds mostly west though north westerly as well coming over the summit, a couple inches of fresh throughout the day. Snowpack stable with no signs of instability stepping off the skin track in a few spots also no cracking or collapsing on low angle glades. ski pen 20-30 cm on top of old supportive surface. Visibility was mostly poor but we did not observe any recent avalanche activity. CBMG Irwin Tenure Weather: Light to moderate snowfall under overcast skies to broken skies. Temps were steady in the mid teens at 10k and near 10F at 12k. Winds averaged around 15mph from NW, with gusts reaching 40 mph. Snowpack: 5†of new snow today (.15 SWE) on top of 5†(.15 SWE) that fell last night. 3% density!! Around our terrain, 8†of low density fluff over the Jan 12th snow which is denser/stiffer. Moderate snow transport with new snow becoming slabbier in the afternoon at upper elevations due to wind. Minor cracking in top 8†on windloaded slopes. No signs of instability below these layers observed today with large explosives that were targeting deep instability concerns on West facing terrain near/below treeline. These areas have all seen heavy early-season use and previous explosive work. Zach Guy
Avalanche
Paradise Divide Area, N-NE-E-SE at 9000-11500 skied 4 runs on Skooks, one skier triggered slide, at low elevation, 300 foot roller 24" deep but super wide, seemed to be r3 the report nailed it, low elevation, seemed to be a possible sun crust facet combo, full east with a bit of south. 1 avalanche observed R1 D1 on the S aspect of Evans basin 10,000. cornice drop the likely trigger. Ski cuts very easily triggered 2 separate fresh shallow windslabs that took out the entire terrain feature and ran debris into the gully. Overall estimated at R4 D1.5