For over 2,000 years, weathervanes have been an architectural staple in cities and countrysides around the world. Today, weathervanes are generally used to add beauty and elegance to a home, but with an understanding of how weathervanes work and your local geography, you can learn to predict the weather like the early settlers.
How Do Weathervanes Work?

To the untrained eye, weathervanes appear to be unbalanced, with one side larger and heavier than the other. Proper balance, however, is crucial to a weathervane’s function. The arrow or figure is the only part of the weathervane that moves, rotating on a vertical axis. The figure is designed so that one side has more surface area than the other, but the weight on both sides is the same.
When the wind blows, the larger side faces greater wind resistance and turns so that the smaller side faces into the wind. Wind direction is determined by where it is coming from. Therefore, if a weathervane is pointing south, the wind is coming out of the south and is therefore a Southerly wind.
When the wind blows, the larger side faces greater wind resistance and turns so that the smaller side faces into the wind. Wind direction is determined by where it is coming from. Therefore, if a weathervane is pointing south, the wind is coming out of the south and is therefore a Southerly wind.
How Do Weathervanes Predict the Weather?
Predicting the weather with weathervanes is something of a lost art. Today, we can turn on the tv and watch a channel dedicated solely to weather, or pull up the weather forecast on our phones with a simple tap of a finger. But just 100 years ago, farmers did not have access to up-to-the-minute weather forecasting. Understanding the wind patterns was crucial to growing a good crop. For example, farmers needed to know the prevailing winds to ensure proper pollination of their fields. They also needed to be sure not to plant their crops perpendicular to constant winds to avoid damage. This information helped farmers orient their fields and know where to plant trees to create a wind barrier.
Beyond that, the winds also helped farmers predict changes in the weather. With an understanding of local geography, the winds provide fairly reliable information. For example, in the Western United States, the following information generally applies:
Beyond that, the winds also helped farmers predict changes in the weather. With an understanding of local geography, the winds provide fairly reliable information. For example, in the Western United States, the following information generally applies:
- West winds generally bring fair skies
- Easterly winds usually bring storms
- In California, northeast or east winds during the summer or autumn are hot, dry winds that can be gusty and strong
- During the winter, north winds warn that stormy weather is approaching, possibly bringing snow
- Southerly winds usually bring warmth, humidity and rain (sometimes gentle, sometimes torrential)
Beautiful, Functional Weathervanes from Valley Forge Cupolas
Whether you are looking for a traditional rooster weathervane or something more nautical, Valley Forge Cupolas has the weathervane that is perfect for you. Call us today at 866-400-1776 to learn more about our easy-to-install, durable copper weathervanes.