Loose Wet
- Alpin
- Limite forestière
- Sous la limite forestière
- Probabilité
- Possible
- Taille
- 1–2
Air temperatures were above freezing last night and the snow surface refreeze was reliant on radiational cooling under clear skies at most locations on the peaks. With colder air sitting on the mountain valley floors, the strongest areas of snow surface refreeze may exist near the trailheads and be weaker up higher. Snow surface refreeze is expected to be stronger on open slopes and weaker and/or thinner under the forest canopy. In all areas the snow surface refreeze will be superficial, temporarily capping residual wet snow below the surface crust that did not refreeze overnight.
Once the surface crust is nearly or completely melted away, the wet snow on the surface will combine with the deeper residual wet snow below it. This will create potentially unstable conditions and allow for the possibility of wet loose snow avalanches. Once the surface crust starts to lose supportability, minimize risk by focusing travel on lower angle sub 30 to 35 degree slopes without steeper slopes above.
(4/9/2021) Multiple recent wet loose avalanches and some cornice fall. NE aspect terrain along ridgeline connecting Mt. Lincoln to Anderson Pk near Donner Summit, CA.