A microburst is a strong and unpredictable downdraft that moves in a way opposite of a tornado. Found in strong thunderstorms, microbursts are either ‘wet’ or ‘dry’ and have been responsible for many airplane crashes. In the video above, we see a dry microburst causing grounded planes on an airfield to inadvertently take off.

Dry microbursts occur when rain falls below cloud base or is mixed with dry air. As it begins to evaporate, this process cools the air. The cool air then descends and accelerates as it approaches the ground. When it approaches the ground, it spreads out in all directions and this divergence of the wind is the signature of the microburst. [source]