What is the highest predictor of avalanche potential?

• A. Critical snowfall rate
• B. Historic avi data
• C. Terrain trap examples
• D. Orthographic lifting

Answer: (B)

In avalanche forecasting, past behavior is the strongest guide to what might happen next because avalanches arise from the combination of snowpack weakness, loading, and terrain, all of which leave a measurable history. Historical avalanche data records where slides have occurred under certain weather and loading conditions, revealing recurring weak layers and vulnerable slopes. That empirical pattern—what has happened in the same area under similar conditions—captures the real behavior of the snowpack more reliably than any single factor, since it integrates multiple influences (snow depth, wind loading, temperature changes, crust formation, and slope geometry) into a visible track record.

While a fresh snowfall rate, terrain features, or orographic loading all matter, they are pieces of a larger story. A high snowfall rate might suggest potential, but without a history of slides or without the right weak layers and triggering conditions, it isn’t as strong a predictor. Terrain traps highlight high-risk locations, not the likelihood of an avalanche occurring across the landscape. Orographic lifting explains how mountains load snow, but it doesn’t by itself indicate whether the snowpack is ready to fail. The historical avalanche record, by contrast, provides a robust signal by reflecting how all these factors have interacted in practice in that area.