Persistent Slabs
- Alpine
- Treeline
- Below treeline
- Likelihood
- Possible
- Size
- 2–3
You can trigger avalanches that fail on weak layers that exist 2-4 ft below the snow surface. It's been several days since the last known persistent slab avalanche in the eastern mountains, but observers as of Sunday reported multiple whumping collapses in the Blewett Pass area. Unfortunately, this structure is widespread throughout the zone and in many parts of the region. Additionally, a layer of buried surface hoar from January 2nd sits an inch or two above a crust from December 30th and has been the culprit of several avalanches near Darland Mtn and the east central. Persistent slabs take persistent patience. So, your best mitigation tool will be to stay off open steep slopes to reduce the odds of you triggering one.
(1/10/2024)
Backcountry travelers near Lake Wenatchee remotely triggered this avalanche from a low angle adjacent slope. This avalanche ran on weak, facted snow over the Solstice Crust.
Photo: Pat Riffie