Plain English Meaning

The wind isn't steady. It's blowing at one speed most of the time but suddenly jumping to a higher speed in short bursts.

Full Definition

In a METAR, gusting describes wind that is varying rapidly in speed, with peaks of at least 10 knots above the reported sustained wind speed observed during the past 10 minutes. It is reported using the letter G between the sustained speed and the peak gust speed (e.g., 18G28KT means wind sustained at 18 knots, gusting to 28 knots).

Context Anchor

Seen in METAR wind groups, such as 27012G22KT, where the wind is from 270 degrees at 12 knots gusting to 22 knots.

Derivation

From the Old Norse 'gustr,' meaning a sudden rush of wind. The aviation use keeps the everyday meaning but adds a specific threshold: the peak must be at least 10 knots above the sustained wind to qualify as a gust.

Why Pilots Care

Gusts can suddenly change lift and control during and , so pilots plan higher and for handling corrections.