Wind Slabs
- Alpine
- Treeline
- Below treeline
- Likelihood
- Possible
- Size
- 1–2
The storm favored the eastern Cascades, and the Green Lake SnoTel picked up over 1 inch of SWE and 13 inches of snow. Strong and complex winds shifted directions frequently, building wind slabs on all aspects and sometimes in unusual locations. On Monday, NWAC staff near the border of the East and West South zones easily triggered wind slabs on opposing aspects along a ridge.
Snow will continue to trickle in, and wind slabs may be harder to identify with a few inches of fresh snow covering the textured surfaces. But some visual clues such as actively blowing snow, cornices, or drifts around rocks and trees can still help identify wind-affected terrain. You can also use your pole or probe to feel for stiffer snow over softer snow. Finding ridgeline terrain that doesn't have a lingering wind slab at upper elevations will likely be challenging. Therefore, stick to lower-angle routes and avoid start zones if traveling in alpine terrain. Look for signs of instability at lower elevations, such as shooting cracks or collapsing, that indicate you should stick to lower angle slopes or wind-sheltered terrain.
Rough surfaces and a thin snowpack limit avalanche potential at lower elevations throughout the zone. Still, the snow has been piling up for the last few days, and you may be able to trigger small avalanches in the new snow, even at lower elevations. Use caution in terrain where a small avalanche could push you into rocks, trees, or other obstacles.
(4/11/2022) Wind slabs were found in some unusual spots. Fresh slabs were observed on slopes often stripped by the wind. Photo: Dallas Glass