In conclusion, the idea of opening your windows during a tornado is a dangerous anachronism, a piece of folk wisdom that has been refuted by decades of scientific investigation. The destructive power of a tornado comes not from a sudden pressure drop, but from the immense kinetic energy of its rotating winds and the cloud of high-velocity missiles those winds carry. Opening your windows invites this destruction inside, weakens your home’s structural integrity, and wastes the precious seconds needed to seek proper shelter. When the sirens sound and the sky turns green, your course of action should be simple and decisive: leave the windows shut, leave the doors closed, and put as many barriers between you and the storm as possible. Get to the basement, the bathroom, or the closet, and cover your head. The only thing that opening a window will do is open you to the very danger you are trying to survive.

Perhaps the most critical reason to ignore this myth is the time factor.

For decades, many believed that the low pressure inside a tornado would cause the higher pressure inside a home to push outward, causing the walls to burst. Science has since debunked this: Tornado Safety Rules - National Weather Service

While pressure differentials do exist, structural engineers have found that they are rarely the primary cause of destruction.