February makes a bridge, and March breaks it.

Late-winter cold may form a passable bridge of ice, only for March weather to thaw or weaken it. The proverb warns that what appears solid during one phase of the season can quickly become unsafe as conditions change; it is not a guarantee that this pattern occurs in every place or year.

Figuratively, it expresses the fragility of arrangements built on temporary circumstances. A solution, advantage, or connection may seem dependable for a short time, yet be undone when the surrounding situation shifts. Its force is caution about instability, not a prediction of a particular outcome.

Use it when a short-lived spell of favorable conditions may soon be reversed, especially where apparent security depends on weather or another changeable circumstance. It can introduce a caution about plans that rely on temporary stability, rather than confidently forecasting how events will end.