A squall is a sudden and strong increase in wind speed that is usually associated with storms, such as rain, thunderstorm, or snow.
Squalls refer to a sustained increase in the wind for a short period of time, since there may be larger gusts during the course of a squall.
This phenomenon usually occurs in regions with strong falls from mid-level heights, or mid-level tropospheric cooling, which forces strong upward movements at the edge of the cooling region, which then induces local downward movements in their wake.
Source: YouTube
