Persistent Slabs
- Alpine
- Treeline
- Below treeline
- Likelihood
- Certain
- Size
- 1.5–3
Most steep slopes are at, or have reached, their tipping point. We expect the mountains to come unglued today and tonight. Large, destructive avalanches will release naturally in areas where they rarely occur. Avalanche crowns could pull into "normally safe" 25-30 degree terrain.
The mountains received 3.5-4.5" of water (35-60 inches of snowfall) in the past 3 days, and we're looking at another 1.5-3" (15-35 inches of snowfall) by tomorrow morning. Precipitation rates—and the avalanche danger—are expected to peak near and after sunset, while winds blow at strong speeds and temperatues approach freezing.
The intense multi-day storm is overwhelming very weak snow that formed during the month long drought, including surface hoar, facets, and facet + crust combinations. These layers exist on many slopes, the weakest of which are found at middle and low elevations. Before the weak layer was buried, it appeared to be one of the worst we've seen in recent years.
The travel advice is simple: stay far away from steep slopes and the areas beneath them.
(2/2/2025) Debris from a large natural avalanche in the Warm Springs Ck drainage near Frenchman Bend.