Two Medicine Valley

Quick report

• Traveled into the Two Medicine Valley for a welfare check on NPS facilities and to collect snowpack data over the weekend. We enjoyed stormy skies, calm winds, and excellent powder skiing. • We favored south facing terrain in order to steer clear of any lingering persistent slab problems on northerlies. We confirmed that the recent heat wave had percolated meltwater to the ground on southerlies up to 7000' but would have liked to investigate the same questions for northerlies. Sunday afternoon, slightly improved visibility revealed several natural dry loose avalanches in terrain steeper than 40 degrees (mid & upper elevations). This activity was relatively widespread in very steep terrain and did not seem specific to aspect. No wind slab or storm slab activity observed. New snow remained unconsolidated through late Sunday.

Weather

Cloud Cover

overcast

Wind Loading

none

Recent Snowfall

38

Snow Avail For Transport

large amounts

Calms winds, light-moderate snowfall, and overcast skies. The bulk of the recent snowfall arrived on March 21st prior to our arrival. During our ski out on Sunday evening the cloud cover was transitioning to broken and the temps were dropping.

Snowpack

• Abundant recent snowfall (15-20 inches) undisturbed by the wind. This new snow is resting on a stout crust that was buried late March 20th (Equinox Crust?) Lean & variable snowpack coverage prior to the recent snowfall. • Around the campground (5200') in sheltered, flat (no aspect) areas, snowpack depths measured between 50cm and 90cm, with the top 38cm being new snow since last Wednesday night, 3/20. • Our upper elevation snowpack observations were limited to southerlies. Snowpack was highly variable in the upper elevations due to significant wind redistribution characteristic to this area and on this windward aspect. We collected a hardness profile from a site that had an average snow depth for the slope. HS=78cm. The lower 19cm at this site was still moist to wet from the heat wave that ended last week. HS at upper elevations generally varied from 50-110cm on southerly slopes. Pit profile attached. • By Sunday afternoon, the storm total had reached 50cm around 7200'. Recent snow remained mostly unaffected by the wind and unconsolidated to this elevation. The top 4 inches of the new snow felt extra dry, sloughy, and faceted on Sunday. Light wind effect observed in open areas near the valley bottom.

Avalanche

Dry Loose on very steep slopes. All aspects mid & upper elevations.