Wind changes direction all the time. Sometimes it changes direction quickly.
When you are on the ground, the wind only changes direction to come from left or right.
When you are up in the air, wind can also change direction to come from up and down as well.
Sometimes, if the wind is strong enough, some of the up and down wind from the sky hits the ground and goes SPLAT!
Here is a cross-section of a gust. The air on the ground is flowing from right to left.
