How can we tell where the wind comes from?

Have you ever stood outside on a windy day? You feel the wind push on your cheeks. You hear it whoosh through the leaves.

But you cannot see the wind at all. So how can we tell where the wind comes from? Let's go to the park and find out.

Picture yourself in the middle of a park. The duck pond sits across from the swings. The big oak tree stands across from the slide. The wind blows from the side of one of these four things.

First, lick the tip of your finger and hold it up high. The wind dries the wet side that it touches. Drying water feels cool on your skin.

Your finger feels cool on the side toward the pond and the oak tree. So the wind comes from one of those two. Your finger cannot tell which one.

Next, look at the windsock, a cloth tube on a pole that the wind fills. It stands right in the middle of the park. Its big end is open like a mouth.

The wind blows into the windsock's open end. Then it pushes the thin tail out the other way. So the open end always faces where the wind comes from.

Look up now. The windsock's tail stretches out toward the swings. Which side does the wind blow from, the pond's side or the oak tree's side?

The wind blows from the duck pond's side! The tail points at the swings, so the open end faces the pond. Your finger and the windsock agree.

Windsock. A wet finger cools on the wind's side, and a windsock's open end faces the wind.

Tomorrow, you can lick your finger and feel the wind yourself. On the next windy day, you will know just where it comes from.