Front Range
AvalancheAndy Whilden · Jan 16, 2023 · Front Range
Weather
Overcast, cold, snowy, windy for most of the day. Skies were cloudy until 2pm and then started to break. The high was mid 20s in the late morning then dropped. Snow accumulation of 2-3 inches during the day. Winds were consistent 10-15mph with gusts of 25+. Below and near treeline on east facing slopes between 10,200 - 10,800 feet.
Snowpack
Snowpit dug below treeline on an east northeast facing slope at 24 degrees near 10,500 feet in a small clearing near the skin track. We did 2 column tests -- First column: 170cm total; shearing at: 155cm, 2 taps at elbow; 145cm, 8 at shoulder; 115cm + 95cm, hard shoulder taps; 50cm, created consolidated block (see Ted's head in comic strip); below was facets to ground. Second column: 155cm total; shearing at: 145cm, 10 wrist; 130cm, 2 elbow; 105cm, 5 shoulder; ground, 12 shoulder creating a 100cm consolidated block (see Ted's body). Observations: In the first column, we found the snowpack to stable and required very hard hits to create significant breaks beyond recent storm snow sluffing. But we did find a 50cm persistent slab buried sitting above 40cm of very faceted snow at ground level. This suggests low probability, but potentially large, persistent slab concerns lurking at the bottom of the snowpack. In the second column, we found the same storm snow sluffing, but then were surprised by a 100cm block breaking just as we transitioned to using harder hits. We noted the second column was about 10% shallower, in large part due to it sitting on a 5 inch log that was not underneath the first column. The entire column broke at this log and was easily movable due to its cohesion. We believe this illustrates the danger of unsuspected shallower spots being sensitive triggers for avys that could break to the ground with a meter thick slab. For us, this clearly demonstrated the low-probability high-risk danger of our current snowpack. Just 30cm difference in location, we created a cohesive block twice as thick with significantly less force. And the blocks (which represent the p-slab problem in our snowpack) were so solid we just had to build a block man -- the avy nerd's snowman -- and created a comic strip to commemorate him (see photos). Takeaway: 50-100cm of hard slab sitting over 40cm of faceted sugar = YIKES!!
Avalanche
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