02-03-05 Eaglecrest

With over 60 cm of accumulated light dry to moist snow on the poor bond of the thaw crust from last Sunday the 30th of January, we stayed inbounds at the ski area today and avoided the backcountry entirely. There has been little wind to trigger an avalanche cycle and create sensitive windslabs so far, but the ski patrol was able to get some sizable slabs to release on the lee slopes that did have some light windloading from SE wind in the last few days.

Snowfall rates have been heavy and there is abundant light snow available for wind transport, so the stronger winds currently forecast to begin late tomorrow can be expected to trigger natural avalanches and to make human triggered avalanches likely in the backcountry.

Most slabs will initiate in the top layer of windslab, but are likely to take out the entire 60+ cm of new snow as well, down to the January 30 crust. There is some chance that larger slides might begin to step down to the weak layers formed by the December 23 - 24 faceted melt freeze and associated facets, making for large avalanches with slab thicknesses greater than 1.5 m.

We did not do a snow profile today, focusing instead on the results of slope tests, explosive work, and ski cutting in the ski area. There appeared to be only a few small skier triggered slides in the area, but larger slides are certainly possible in areas with more windloading.

Marc Scholten demonstrates how tree wells can become traps for snow travelers when new snow is deep and loose.
Explosive triggered stepped slab in the East Bowl Chutes area near shot points C 9 - 11, a lee slope lightly windloaded by recent SE winds coming over the row of trees at the left.
Another explosive triggered stepped slab, just below the other slab near shot point C12, on a similar lightly wind loaded steep slope. Fractures were initiating in the soft surface windslab layer, then stepping down to the January 30 faceted melt freeze and associated facets.
Marc finds deep powder in the East Bowl Chutes.
Marc skis a last run as the snowfall rate increases again. Large clusters of lightly rimed dry stellar crystals and fragments were falling at rates up to 5 cm/hr during snow shower periods today.