When do avalanches most likely occur after snowfall?

The most likely time for avalanches to occur after snowfall is within 24 hours. This window is critical because the new snow can create instability in the layers beneath it. During this period, the weight of the fresh snow may not have settled or bonded well with the underlying layers, leading to potential sliding.

After the first 24 hours, the snow begins to undergo changes due to temperature and settling, which can sometimes increase stability, although it always depends on other environmental factors. In contrast, snowfall that occurs immediately may cause a heightened risk of avalanches as the snow does not have the time to stabilize, making this timeframe crucial for assessing avalanche danger.