Date of Observation: 11/15/2017
Name: Ben Pritchett & Eric Murrow
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Weather: Partly cloudy sky and generally calm winds with moderate gusts from the southwest. Enough solar to warm snow surfaces in low angled terrain and southerly facing slopes, mostly below 11,000ft.
Snowpack: Just a dusting of new snow from recent days. So, little change to the slowly developing snowpack. Thin and isolated would be my best short answer description of the current snowpack. Generally thin snow cover with isolated avalanche potential on wind loaded terrain. Snowpack structure is highly variable through the terrain. From bare ground or very thin snow coverage on southerly slopes, wind scoured on many south westerly to westerly slopes, to just a thin snowpack on the other aspects. There is very little to no snow on all aspects below 10,500ft. The deepest snowpack could mostly be found on northwesterly to north facing slopes above treeline that are either protected from the wind or have seen additional wind loading during previous storms. Faceted snow from October is the weak layer at the bottom of the snowpack and can be found where it hasn’t been blown away or previously melted by the sun. Find a thick enough slab on top of this week snow and you’ll have found a potential avalanche problem. These two ingredients looked to mainly line up on wind loaded terrain. Such as, cross loaded gullies on westerly aspects or wind loaded pockets on northerly and easterly aspects.
Avalanches: At 1:45 PM I triggered a shallow but wide (70m+) slab avalanche while skiing alone on the NW aspect of Mt. Baldy. I was alone because I was really just out for a tour on the roads. But I had bootpacked up to Baldy’s West ridge for the exercise, in very shallow snow/talus, and I was planning to sideslip back down a trough and then do a descending traverse back to the road. As I traversed out of the trough onto an open slope of about 25 degrees, I heard the snow wumph then immediately saw cracks form above and all around me. Before I could do anything, a wide swath of the slope cut loose and slid, with me approximately in the middle. I was still on my feet, so I skied with it, heading down but slightly across it for about 20 meters before I reached stable snow. Luckily the slide was relatively slow and shallow (4-6″), with no trees, rocks, or obstacles in its path. It slid for about 50-60 meters before stopping.
Weather: strong, gusty winds from the southwest, blowing snow, occasional snow showers
Snowpack: 6-10″ windblown surface with some softer snow in troughs
Avalanches: None, Just whumphing on a 30 degree protected pocket.
Weather: Cloudy and snowy with winds blowing 10-15 mph to the North West with gusts in the 30’s. Maybe 28 degrees F.
Snowpack: Snow depth in a wind-loaded gully ranged from 35-75 cm deep. The protected bottom of the very small north facing gully contained most of the snow we saw in October and that’s where we were seeing positive results with our collum test. The nonprotected section of the pit outside of the gully was mostly this week’s new snow. There were almost 7 inches of new snow some of which was from wind loading blowing across the gully.
We remote triggered cracking from 15 meters away at the top of a very small convex roll from the bottom where we were skinning. A big whumph occurred so we decided to dig a pit and do a collum test. Surrounded by grass and on a small pitch of about 30 degrees at the very bottom of Paradise Bowl (Paradise Divide Bowl), we felt good about where we were. The test produced a positive result at 11 taps about a foot into the snowpack. The slab was failing on that mid-October storm layer. it just took a little weight to wake it up. Extremely rotten facets are littering the snowpack right now.