Wind vanes are simple in design-they consist of an arm with a fin on one end and a pointer on the other. Wind VaneĪ wind vane (also known as a weather vane) is an instrument that shows you the direction of the wind. The most common way of measuring wind is by using a wind vane. Thus, a northerly wind blows from north to south, a westerly wind from west to east, and so forth. It’s important to remember that the measured wind direction is where the wind is blowing from, not where it’s blowing to. Wind direction is an essential measurement to meteorologists because often the wind direction can provide clues to future weather.
These days, a computer counts the rotation and makes the calculations for us, simplifying this process. Traditionally, meteorologists had to do this count, which was sometimes very difficult to do in windy conditions. As the wind blows, these cups spin and the number of times they rotate around is counted in a single minute, which is then converted to wind speed. It contains either three or four cups, conical or hemispherical, placed on their sides and attached to a central mast that can spin freely.
The cup anemometer is the traditional instrument used to measure wind speed. S o, how are wind speeds measured? The instrument we use is called an anemometer, and there are two primary types.
It’s an average of the wind speed over the past two minutes, calculated from a series of 24 five-second average values. It’s important to mention here that the wind speeds you see on your nightly weather report are not the exact wind speed at any given time. A knot is equal to one nautical mile per hour, precisely 1.852 km/h (approximately 1.15078 mph). In maritime and aeronautical applications it’s measured in knots. In the United States and the United Kingdom, it’s measured in miles per hour, and elsewhere in kilometers per hour. Wind speed is a measure of how fast wind moves.
See our buying guide for suggestions on which one to buy or learn more about weather stations in this article. You can do this at home by purchasing your very own personal weather station. Keeping track of the wind and the weather conditions that follow can help you predict incoming weather by merely observing how fast and from where the wind is blowing.
Winds are often light under the influence of a high-pressure system, while low pressure typically brings windier conditions. The speeds at which these winds blow vary. In the eastern United States, east winds bring moist air and west winds drier, with the opposite happening in the West. The speed and direction of the wind can hold vital clues to understanding the weather, and even play a role in forecasting future conditions.įor example, here in the Northern Hemisphere a southerly wind often brings with it warmer air, while northerly winds typically usher in cooler air. Wind speed and direction are two of the many variables that meteorologists keep track of when observing the weather.