Quick report
Great to see snow falling back at the pass. Unfortunately, the southerly flow is bringing with it some warm moist air and producing rain as it rises over the mountains. Accumulations of 3-6 inches at Frostbite and Independence Mine respectively feel more like 2-4 on the ground now that the new snow has been tamped down and capped with a fragile crust by the rain. Thankfully the crust isn't all that stout and can be managed with some aggressive turning. Snow is forecasted to continue through tonight which I would expect to translate to an increasing soft slab and dry-loose problem both on the old snow surface and possibly on this new rain crust. Today it seemed like the new snow wasn't contributing to much hazard at low or mid elevations but the story could be different on upper elevation ridgelines where a little less rain and a little more wind could be working to slab up the new snow.
No instabilites observed.Weather
- Air Temp
- 20's
- Cloud Cover
- obscured
- Wind Loading
- none
- Rain Elevation
- Up to 4000 ft at least.
- Recent Snowfall
- 15
- Snow Avail For Transport
- small smounts
At 10am IM Snotel was reading 6 inches of new snow with light to moderate winds out of the SE on Marmot Ridge. On the way up to the pass, snow gave way to rain pretty soon after crossing the Little Su. Temps readings from the car steadily climbed from around 18° in the valley to about 25° at the pass trailhead. A light drizzle had settled the new snow to about 3 inches and formed a brittle crust on top. Skies were obscured and a mix of light snow and rain fell throughout our walk. Visibility and definition were poor. Outside of a few light gusts winds on the walk were mostly calm.
Snowpack
Unfortunately, our new snow has been settled and capped by a brittle rain crust. This makes the reported 6 inches feel more like 2-3 through mid-elevations. Outside of this crust, there's not much weight to the new snow and it seems to be bonding to old surfaces well, although visibility was limited and we didn't get on anything steep or explore any aspects where old surface facets might have been preserved. In the snowpit, the only instability observed was the inclination for the surface rain crust to slide on the new snow after isolation of the column. Shovel shear test yielded moderate results on mid-pack facets where we've recently been seeing propagation but had no CT or ECT results on this layering today. For now, this rain crust isn't doing anything to change the instability in the new snow, it only serves to degrade the riding conditions. This could change if accumulation continues as forecasted.