Why does wind inside a stadium blow opposite the wind above the stadium?

Question

In a (American football) bowl stadium, the flags on top of the goalposts typically fly in the opposite direction of the flags above the stadium, particularly when the wind is blowing heavily. Why is that?

In: 0

Answer 1

Think of an ice cream scoop. The stand roofs do kinda the same thing to the air.
Similar thing to wind blowing against a tall building, where a part of it shoots up and some of it shoots down the face of the building messing up the umbrellas on the sidewalk next to it.