Vail & Summit County
AvalancheAndrew McWilliams · Mar 21, 2023 · Vail & Summit County
Weather
Skies were overcast to broken with intermittent periods of light snow; there was no accumulation during the day. Winds were light with moderate gusts from the southwest and temperatures were in the high teens and low twenties.
Snowpack
On the Meadow Creek Trail below about 11,000 feet the snow depth was about 100cm. At about 11,000 feet this depth increased to about 150cm. At 11,500 feet on the east ridge of Eccles Peak, the snow depth was over 200cm in most places. In a snowpit on an east aspect, there were a plethora of melt-freeze crusts sandwiching decomposing grains for the top 40-50cm of the snowpack. The next 30-40cm had rounded grains sandwiched by melt-freeze crusts; some with thin ice layers within them. Below 150cm, the snowpack transitioned to thicker layers of rounded grains one-finger to pencil hard on the Hand Hardness Scale. Extended Column Tests (ECTs) had moderate to hard non-propagating results at below crust layers in the upper 40-50cm of the snowpack. A snowpit on a north aspect at a similar elevation also had melt-freeze crusts sandwiching decomposing grains in the upper 30-40cm of the snowpack. However, below this level, it transitioned to one-finger to pencil hard rounded grains. ECTs had similar results, with moderate to hard non-propagating scores associated with crust layers in the upper 30-40cm of the snowpack. Overall, the snowpack was supportable for uphill and downhill travel. Some of the crusts near the surface broke under my skis as I traveled, but I did not sink more than 30cm into the snowpack at any point. No cracking or collapsing were observed, however, on a small, very steep test slope the top 10-15cm of surface snow slid off on a melt-freeze crust layer. This small slide did not propagate very far beyond my ski tips. Some recent avalanche activity was noted on steep east and north-facing slopes near treeline, likely running earlier this month. A large avalanche was noted below a large, steep south and southeast-facing slope on Buffalo Mountain, however, the debris looked much older and the timing of this slide was difficult to discern.
Avalanche
I observed avalanches that likely ran within the last two weeks near treeline on east and north aspects to the north and east of Eccles Peak.