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Observation: Northern Bear River Range

Observation Date
12/22/2022
Observer Name
Eric and Amy Flygare
Region
Logan » Northern Bear River Range
Location Name or Route
Northern Bear River Range
Comments
We decided to get out on this bluebird day and check out the damages from yesterday's storm… Last week's excellent powder is gone with the wind and replaced but wind jacked snow and hard slabs. We were not able to find any snow that was unaffected from the wind. There were trees down everywhere from the wind, and debris from the wind all around.
Surprisingly, we did not see any recent avalanche activity. Maybe there were natural avalanches during the storm and the evidence was covered by blown in snow but I was surprised that we didn't see more red flags. The closest thing we saw to an avalanche was a large crack under some cliffs near a river (see first picture).
We dug several pits to check snow stability:
Pit #1: This pit was dug on a 25 degree NNE facing slope at 8800 feet elevation. I found an area in the trees that was somewhat protected from the winds however the snow was still very wind affected. There was a total of 78 inches on the ground. The shovel shear test popped out a 1 foot deep section while sliding the shovel into the snow. Compression tests resulted in failures at 11 taps about 13 inches down from the surface. The Extended Column test resulted in a failure at 3 taps down 4 inches (ECTN3) and 11 taps down 13 inches (ECTN13). Other than those two failures that did not propagate, I could not get the old Persistent Weak Layer (PWL) to fail no matter how hard I hit the shovel (see pictures 2)
Pit #2: The second pit was dug on a 25 degree slope on an ESE slope at about 8600. There was a total of 54 inches of snow on the ground. The most reactive layer was 12 inches down (buried surface hoar?) The Extended Column Test produced a failure at 18 taps on the reactive layer at 12 inches (ECTN18). It propagated half way through the column but not all the way. This same layer was very reactive during the shovel shear test so it was surprising that it was less reactive durian the ECT test
Amy did get a fairly large woopfh while riding a NE facing slope near 9000 feet.
Today's Observed Danger Rating
Considerable
Tomorrows Estimated Danger Rating
Considerable