Trenchtown in Cement Creek

CB Avalanche Center2017-18 Observations

Location: Cement Creek Area
Date of Observation: 02/14/2018
Name: Ben Pritchett

Subject: Trenchtown in Cement Creek
Aspect: North, Southwest, West, North West
Elevation: 9,000-12,000′

Avalanches: One recent Persistent Slab avalanche off Hunters Hill that gouged down into the depth hoar. East southeast aspect, 12,200′. Given the recent drifting and how sharp the crown appeared through binoculars, I’d guess the slide ran during Monday night’s wind event.

Weather: Warm, breezy day, with looming low dark clouds. PM winds picked up and began to transport snow efficiently near and above treeline. Snow showers rolled in around 2pm, though no significant accumulation.

Snowpack: Very weak, largely unsupportive. Sledding out the valley floor was total Trenchtown. With Al Smith’s grooming (thank you Al!!!) travel was very easy to Hunter Creek, but we didn’t dare leave the road for fear of pegging rocks. Beyond Hunter Creek the snowpack was 60-80cm deep and marginally supportive, requiring good balance and light careful throttle. It would be easy to dig a deep hole for yourself out there given how weak it is. Huge differences in snowpack strength with aspect and drifting patterns.  We measured .75″ of SWE from this week’s storms, compared to 1.75″ of SWE measured yesterday in Pittsburg.
Sunny south to west slopes – Thin crusts mid-pack kept ski pen from going to ground. Several moderate collapses above 11,500′ as we got into wind effect, with consistent cracking under skis. HS ranged from 30 to 70cm, avg. 60cm. Little concern for problems in the short term on these aspects with the forecast for strong southwest to west winds.
Shady west to north slopes – Deeper, with HS 60 to 120cm, avg. 90cm. Very weak. Without wind effect, ski pen was over half the snowpack, trenching on sled or skis. In drifted spots ski pen would rise up to 10cm (ahhh, the trailbreaking was so much easier). Got into some steep north facing terrain and pushed on some wind drifts. Had one slope fail, with cracks extending about 200′ downslope and the snowpack displacing an inch or two downslope but stopping. It was literally on the verge of avalanching, but not quite enough load.  As we skied below the drifted portion of the slope, the slab quickly tapered and inconsistent trap doors opened and closed from local drifting patterns, making for deep but highly inconsistent pow skiing.  As we got below treeline and out of wind effect the homogenous facet beds topped with storm snow made for more consistent turns.

Overall, this snowpack is super weak and teetering on the brink of avalanching where recent winds have formed slabs.  Outside of the drifted areas, it’s simply weak and slab-less.