|Both the speed and direction of the wind are important when observing the weather. An instrument called a wind vane tells the direction of the wind, and an instrument called an anemometer measures the speed of the wind. These instruments can come in different shapes.
A wind vane is simply a piece of specially shaped metal or plastic that is mounted on an upright rod or axle so it can spin freely when the wind blows against it. Because of its special shape, one end of the wind vane always points in the same direction that the wind is blowing from.
To determine from what direction the wind is blowing, compare the wind vane to a compass reading.
One type of anemometer measures wind speed using a hollow tube that is open on both ends, with one end of the tube lower than the other. The outside of the tube has marks measuring miles per hour (MPH). As wind blows through the tube, a lightweight ball trapped inside blows from the low end of the tube toward the high end.
Another method for measuring wind speed and direction is the wind sock. Wind direction is indicated by the direction in which the sock points, and wind speed is indicated by the elevation of the sock towards horizontal. This device is often seen at airports.