Northern San Juan
AvalancheJeff Davis · Mar 11, 2020 · Northern San Juan
Weather
A mix of snow and rain across the highway corridor. The rain/snow line ~9,000'. Winds were light at pass level while temperatures hovered near and just above freezing. Heavy snowfall rates and large snowflakes observed in short bursts. When it wasn't raining it was foggy.
Snowpack
In general the snowpack is thin, weak, disconnected, and wet. There is more snow towards the summit, and less snow to the south. I am guessing the snow in the upper portions of the Peterson remains winter-like, but Yellow Spring wall and Gully are melted out. Snow surfaces have significant roughness and most sunny slopes are back to bare ground. Today, the master stakes were measured at White Lizard- 42" Burn-30". South of Rico the snowpack is fully saturated. A Wet Loose Cycle was observed that the CDOT guys told me happened Sunday the 8th. Wet avalanche were failing at the ground, but small due to lack of depth. Digging on a commonly used test slopes near Scotch Creek the surface of the snowpack was a 15 cms knife hard melt-freeze crust and that crust sits above fist hard wet grains to the ground. The crust broke and didn't propagate on an ECT, but appeared to be fragile and would be an issue with a significant load.
Avalanche
Small Loose Wet Cycle observed that occurred on 3/8/2020.