The avalanche danger increases with major snowstorms and periods of thaw. About 2,000 avalanches are reported to the Avalanche Center in an average winter. The most avalanche-prone months are, in order, February, March, and January. Avalanches caused by thaw occur most often in April. Avalanches can run, however, on small slopes well below timberline, such as gullies, road cuts, and small openings in the trees.
Most avalanches occur in the backcountry, outside of developed ski areas.
But small avalanche paths in the trees can be just as dangerous. Slope angle is the most important factor, so you should carry a slope meter. You also need to observe snow deposition patterns and the effects of anchors such as rocks or trees that might prevent avalanches on some slopes. Finally, bent or damaged trees are good clues that show where avalanches have run in the past. You can reliably avoid avalanches by recognizing and avoiding avalanche terrain.