20-21

Went for a tour today in the Green Lake/Mt Zimmer area. We found around 20cm new snow that was mostly well bonded to the old snow surface. Snow depths are generally over 120cm, but as expected there are thin areas. We dug a pit in one of those thin spots at 10,000 ft on an E aspect, with HS around 110cm. We found the new snow to be sitting on a layer of larger (1-1.5mm) NSFs, and got an ECTN 20. The remainder of the snowpack to the ground consisted of faceted crystals 1F-4F in density. Stability is good for the moment across the area we observed, although the new snow sluffed easily on 40 degree slopes on a SW aspect later in the day after significant warming. We did not observe any collapses, cracking, or signs of slab avalanche activity (1x Natural D1 Dry Loose observed in steep S facing terrain 11,000 ft, 1 ASc D1 in similar terrain).

I took a ski up Abiathar today, and have mostly good things to say. I dug a hand pit at the base of the apron below the north face (~9200’) and found preserved surface hoar about 20 cm down. A pit at the base of the north face (~9500’) was 175 cm deep, and gave an ECTN18 on a couple centimeters of small facets about 20 cm down.

I took my shovel and was able to wobble the entire column back and forth a dozen times or so without it fracturing, so the snowpack there seems to be well-consolidated, for now. I don’t know how widespread the surface hoar and facets are, but they seem to have been buried around the same time, and will be worth digging around for once we get some more snow.

A skier saw this avalanche get triggered at Bridger Bowl (Schlasmans Lift) this afternoon 12/2/2020. "...The toe of the slide was all of 6’ deep. There is about a foot of fresh sitting on top of faceted crust that is sitting on top of more facets and another crust,..." Photo: Anonymous

Hey I just wanted to quick send you this photo of a skier triggered avalanche “in bounds” at Bridger Bowl (Schlasmans Lift) from this afternoon. I was skinning up the N subridge to the lookers right of the lift and some skiers above me triggered a wind slab on faceted snow that came down almost right on top of me. I had to run on my skins to get out of the way. I dug 3 pits yesterday and got ect1 every time so was up skiing and skinning conservatively which allowed me to get out of the way of the slide in time to avoid being caught and most likely buried. The toe of the slide was all of 6’ deep. There is about a foot of fresh sitting on top of faceted crust that is sitting on top of more facets and another crust, and obvious red flags from wind affect (big ripples, obviously wind loaded slopes, obvious slabs forming that you can break through with your skis) - the snowpack is trash! And people are going nuts, skiing dangerous terrain all over the place up there. Just want to remind people to be aware of what’s going on around you, the fact that there could be someone above you at any time, the snowpack is weak, and there is no avalanche control being done up there right now! You can see in the photo that the slide takes out the skin track, so just because there is a skin track doesn’t mean it’s safe! Ok end rant.

Dave Zinn finds a thin snowpack on the east side of Beehive/Bear Basin divide. It consists of weak, sugary grains of facets, a potential problem when it snows again. Photo: GNFAC

Dave Zinn looks at weak snow on our skin up the west side of Beehive Basin. We found mostly sugary, faceted snow that will become a problem when it gets loaded with snowfall. Photo: GNFAC