Snowfall level
Precipitation & snow snow level
The snowfall level is approximately the height above which precipitation falls mainly as snow. It is a transition zone that can move while precipitation is falling.
The flake’s journey matters
A snowflake from a cold cloud may pass through warmer air on its way down. Melting requires time and heat. Flakes can therefore sometimes reach the ground even when the local thermometer reads a few degrees above zero.
Why the level moves
- Temperature and humidity: Affect how quickly flakes warm and how much evaporative cooling is possible.
- Precipitation intensity: Melting and evaporation can cool a layer, allowing snow to reach lower elevations during heavier precipitation.
- Air layers and terrain: Warm layers, valleys and hills alter the transition.
Snowfall level is not freezing level
The freezing level marks air at 0 °C. Snowfall often extends below it, but the gap is not fixed. The snowfall level also does not say where a continuous snow cover will settle.
A useful regional example
When the snowfall level lies between a valley and higher ground, it can rain below while snow falls above. This is an example, not a fixed rule. Whether paths turn white also depends on ground temperature and the intensity and duration of snowfall.