Loose Wet
- Alta montaña
- Límite del bosque
- Bajo el límite del bosque
- Probabilidad
- Likely
- Tamaño
- 1.5–2
Loose snow avalanches are likely on very steep, rocky slopes receiving direct sun. These slides often initiate near the base of trees and rocks, gathering snow and growing in size as they move downhill. Rollerballs, or pinwheels, signify that the snow is heating up, and wet avalanches may soon follow.
While most will start small, they may will grow large and dangerous or push you into unwanted terrain. Some slides have the potential to flank out into wider wet slab avalanches. Even small slides are consequential above terrain traps such as gullies, creeks, and thick timber. Plan your day to avoid lingering under steep, sunny slopes when the sun is out.
Additional Discussion - Wind Slabs: You may find lingering wind slabs near ridgelines and along steep mid-slope gullies. In many places, wind slabs may be difficult to trigger but could pack enough of a punch to knock you off your feet and carry you where you don't want to go—especially in extreme terrain. You can reduce your chances of triggering a wind slab by avoiding slopes with obvious signs of wind-loading, such as new cornice growth and large dunes or pillows of wind-blown snow. Cornices are large and may be unstable. Warming temperatures may cause overhanging cornices to sag and fail. Limit time beneath these features and give them a wide berth when traveling along ridges.
(2/26/2025) Wet snow avalanches in the Marshall Lake Basin. Sawtooth Mountains.