We toured east of Whitefish Mountain Resort, in the southern Whitefish Range, to assess the distribution of the 1/13 crust and to look at the recent avalanches.
We found 3” of new snow on varying surfaces. On south facing slopes, it was dust-on-crust; the rain crust from 1/13 is still very firm and sitting just under the new snow from today. On north aspects, there was 2”-3” of wind blown snow between the crust and today's snow today. The crust is not as robust, until below about 5500 feet.
We were able to trigger small dry sluffs in steep terrain on both N and S aspects. With more loose snow on the crust, these would likely run far and fast.
The new snow was not wind affected and did not crack.
We dug a pit on a SE aspect at 6334 ft and found a surprisingly shallow snowpack with a depth of 125cm. Our ECT block failed on isolation at a crust-facet combo at 81 cm above the ground. We also had an ECTP at 25 cm above the ground on another crust facet combo. Even though these results seem concerning it would be hard to imagine a skier impacting these layers through the stout crust on S aspects.
On a W aspect, we saw many crowns from the recent cycle. It looked like at least 8 large (D2) avalanches had run during the night of the 12th, many of them contiguous to each other. If you added up the slides, they would be the equivalent of an R4. This terrain does not usually avalanche. At a crown the snow had failed 48cm (including today's snow) down on no distinct week layer in the snowpack. We got a CTX at the crown.
Slope angle seemed to play an important role in this cycle; most of the crowns we saw were steeper than 40 degrees.
Coming out of the Canyon Creek road it was impressive how much of the terrain on both N and S aspects had slid. There were at least a dozen D-1 to D-2 slides and two large D-3 slides that ran in the Skook chutes entraining trees in their path depositing debris on the road.
A rider reported 3 very large natural avalanches further down the canyon, that ran off the ridge between Canyon and Kimmerly Creeks (photo).
Since the new snow was not wind-affected and the crust was always present we felt safe skiing terrain steeper than 35 degrees on both N and S facing aspects.
Many slides on all aspects, mostly D1, to D2. 2 D3s that ran in the Skook Chutes.
Have never seen slides on many of those slopes. Many crowns visible in small openings in trees. Most crowns/ debris on or below very steep slopes (40*). Round debris with rain crust. Looks like many slides entrained wet snow as they ran, though slabs may have been dry slow or with just rain-soaked surface. Some large trees across the canyon from the debris oiles had snow packed on the trunks, possibly from airblasts.
Secondhand report, with image.
