Persistent Slabs
- Alpin
- Limite forestière
- Sous la limite forestière
- Probabilité
- Possible
- Taille
- 1–2.5
Human triggering large persistent slab avalanches are possible, especially in sheltered areas at treeline and below.
Strong west wind may form reactive wind slabs in open terrain.
At treeline and below, persistent slabs sitting on a weak layer of surface hoar are possible to human trigger.
Human triggering large persistent slab avalanches are possible, especially in sheltered areas at treeline and below.
Strong west wind is building wind slabs farther downslope than usual.
On Monday, a naturally triggered size 2.5 wind slab was reported on a north aspect in the alpine.
Additionally, several naturally triggered persistent slabs up to size 1.5 were reported near Golden. They were failing on a layer of surface hoar down 30 to 40 cm and occurred on primarily north and east aspects below 1900 m.
10 to 20 cm of recent snow accompanied by strong southwest wind has formed deeper deposits on north and east aspects. In sheltered terrain it will overlie a variety of surfaces including surface hoar, facets, and a sun crust.
There are 2 prominent weak layers in the upper snowpack
A surface hoar/crust layer buried early to mid-February is down 15 to 30 cm.
A facet/crust layer buried at the end of January is down roughly 20 to 40 cm.
Below this, the mid and lower snowpack are well settled with several crust layers.
Tuesday Night
Partly cloudy. 50 km/h west ridgetop wind. Treeline temperature -9 °C.
Wednesday
Mix of sun and clouds. 60 km/h west ridgetop wind. Treeline temperature -9 °C.
Thursday
Mostly cloudy. 2 to 5 cm of snow. 70 km/h west ridgetop wind. Treeline temperature -6 °C.
Friday
Mix of sun and clouds. 60 km/h west ridgetop wind. Treeline temperature -5 °C.
More details can be found in the Mountain Weather Forecast.