What is the definition of a squall?

A squall is defined as a sudden and brief increase in wind speed, specifically characterized by an increase of at least 16 knots that lasts for a duration of at least one minute. This phenomenon is often associated with thunderstorms or rapidly developing weather systems, where strong winds are a significant feature. The sharp increase in wind speed can often be accompanied by precipitation, turbulence, and changes in visibility.

In this context, the other options do not accurately describe a squall. A sudden drop in temperature, while perhaps indicative of changing weather, does not define the wind characteristics that identify a squall. Likewise, a gentle breeze with rain or a steady rainfall without wind changes does not capture the sudden and notable gust aspect that is central to understanding a squall. Thus, the definition focusing on a specific increase in wind speed is what makes it correct in identifying a squall.