West Brush Below Treeline Observations (Grand Traverse Course)

CB Avalanche Center2018-19 Observations

Location: Brush Creek Area
Date of Observation: 03/25/2019
Name: Ian Havlick

Subject: West Brush Below Treeline Observations (Grand Traverse Course)
Aspect: East, South East, South, South West
Elevation: 9-10,000


Observed 4-6 D1 wet loose avalanches near treeline on southeasterly Whetstone near cliff bands mid afternoon yesterday. otherwise no recent significant activity noted

Weather: Warm day, fog dissipating by 1300. Mild temperatures, but did remain in 20s until midday. The fog increased “greenhousing” along edges of cold pool and increased snow warming, but in the valley bottoms where fog was thickest, fog kept lid on warming until it burned off. Winds were light and variable, but at higher elevations, did look like snow was being blown around on Whetstone form the west.

Snowpack: Continues to transition to a large grained, spring snowpack at lower elevations and terrain traveled today, but lower elevations southerlies are not quite there with plumbing established to move water quickly through the snowpack. In an 80cm profile near West Brush creek, the upper half was large grained and consistent hardness, but the lower portions of the profile were moist, smaller grained, still closer to winter-like snow. It was the densest portion of the profile that was resting immediately above very weak, unconsolidated grains near the ground. Wet slab structure is not striking, but does look like it has characteristics that could produce wet slab during warm afternoons. Some informal shovel shears to check structure revealed moderate but clean failures mid-pack, and near the ground. Did not take time for compression tests as the snowpack was rapidly warming and changing and did not feel test scores would be super relevant at later times of day.