Lull

A temporary reduction in wind speed.

A lull may last only a few seconds or persist for longer between gusts or during a broader change in the weather. It can alter sail force, apparent wind, boat speed and balance, particularly when the surrounding wind is variable.

The term describes a decrease rather than a forecast of what follows. Wind may return at its previous strength, increase in a gust or continue to fall, so sail handling and manoeuvres should not assume that a lull will last.