Rare chance to see our backcountry snowpack tested with more than body weight today. It didn't flunk. But it didn't hold up well.
CliffNotes: The snowpack is still failing near the Jan. 13 crust, and the failures are propagating long distances and producing very large avalanches. Yet not every slope will fail under a rider's weight. Slopes less than 35 degrees seem to be releasing less regularly.
This combination - very large triggered slides, tested slopes with no results, and little natural activity - leaves us in a difficult, disturbing scenario. It's particulary disturbing because these start zones are unlikely to harbor the late January surface hoar. These slides likely failed on facets above or below the 1/13 crust. Which means the persistent slab avalanche problem is serious on all aspects above about 5500 feet.
The implication for backcountry riders is pretty clear: hit the wrong spot on a slope, and it'll trigger a terrifyingly large, likely unsurvivable avalanche. Miss those spots, and you'll wonder what all the worry and fretting is about. Since we don't have x-ray goggles and can't see those spots, sticking to low angle slopes (less than 30 degrees. 30*!! not 35*) is the only way to ensure we don't release a slide even if we do collapse and crack a slab.
Oh, and more snow and wind are on the way. This hazard will linger for awhile.
Shed 7 West. Much of crown right under cantilevered cornice, with upper most point up to 15 feet deep. Crown propagated blow bench, into less-wind loaded terrain, where it looked to be about 4 feet thick. Released 11:00 am, give or take a few minutes. Debris ran over Shed 7 but did not reach creek.
Noticed morning of 2/24 on face of Rampage Mtn. Crown relatively dee, but not wide propagation.
1163 Path. Long, straight crown running up slope parallel w rocks above. Possibly broken at one point, so possibly 2 slides. Debris stopped on cutbank above railroad grade.
Shed 9 Path. Ran to within 100 feet of shed.
Shed 7 East. Wall-to-wall. Debris ran over shed and dusted Highway 2.
Forecast Hotline: 406.257.8402
Call or text an observation: 406.66AVYOB