Southern San Juan
SnowpackBill Nalli · Mar 1, 2020 · Northern San Juan
Weather
Light snow began before noon and wind was moderate to strong at times. Snowfall was intermittent until about 1pm and then picked up for a couple hours. Accumulation of 1 inch in wind sheltered locations but wind transport was drifting snow onto NE aspects where up to 3 inches was measured by 3pm.
Snowpack
Lots of crusts and stable snow on all southerly and east facing slopes from the road to the ridge. The new snow is not bonding as well as the last storm that came in a bit warmer. The crust at the surface has already refrozen and should provide a slick sliding surface. No instability currently until we get a slab on top. Where the new snow was being blown into drifts on easterly facing terrain a shallow slab is forming. I witnessed a very small D1 loose-snow avalanche come out of the East Turk Couloir (over 40 degrees) that ran fast and far for such a small amount of snow. It may have been large enough to knock you off your feet which would not be good in this type of committing terrain. Of note down lower on a southeast aspect at 11,400' I found very weak 4-finger to fist hard rounding facets near the ground with a series of frozen crusts above it and at the surface. See snow profile and photos of percolation columns that have begun to form. This structure is not currently a problem as it is in its very strong frozen state. If we were to get a strong warm up in the near future that softened the crusts and made the pack isothermal, wet avalanches would be likely where this type of structure exists.