The Aerovane, also known as a Propeller Anemometer and a Windmill Anemometer, is used to determine both wind speed and wind direction. Unlike cup anemometers (save for the one invented by Derek Weston in 1991), the Aerovane in all its forms (and names) is a mechanical velocity anemometer.
The platform midway up the structure shown in the photo I took on the left is a point at which the observer can lower the top half of the pole to change the red light bulbs at the top, also known as the Crow’s Nest. The aerovane on this tower is approximately 75 feet above ground level (agl).
The aerovane in the photo I took to the right is a second unit located atop our MetData1 automated station. It sits approximately 15 feet above ground level. Both units measure wind speed in miles per hour, and direction in degrees of the compass.
~ Steve Woodruff and Devin Lussier