Guide to Homemade Weather Stations

Homemade weather stations are the result of assembling a handful of different instruments for measuring the weather. The station's instruments are analog for the most part. They are usually assembled into or mounted on box that is open on one side. Sometimes these stations even have small peaked roofs, which better enable them to endure the weather. Set up in places that have good exposure to the weather, they are often found on the tops of buildings or fixed to posts in open fields. Using stations of this kind, very reliable data about the weather can be collected and used to make predictions.
The Barometer
The barometer is an instrument for reading air pressure. Falling air pressure usually indicates an impending storm. Barometers are typically included into homemade weather stations by hanging a wall-mounted unit inside the station box. This protects it from wind and rain, but because the box is open on one side, the barometer can still take accurate atmospheric readings.

Wind Measurements
Homemade weather stations typically include a weather vane, an anemometer, or a machine that incorporates both into the same device. This takes readings for both wind direction and speed. Analog anemometers are simple machines that work somewhat like a wind turbine: the wind spins the cups or rotor, which generates a small electric current. The strength of that current directly corresponds to wind speed on a pre-established meter. Weather vanes are very simple instruments that turn to point in the direction that the wind is blowing.

Precipitation
Rain and snow meters are simple, clear tubes that capture the relevant precipitation. Sometimes both instruments are combined into the same tube, simply by printing two different gauges on the side. The tube's size and its gauge(s) are calibrated to offer a simple to comprehend figure on rain or snowfall, which in the United States is stated in terms of inches.

Temperature
Adding a thermometer to a weather station is a simple matter. However, a complication is that while putting a thermometer inside the weather station box will protect it from the elements, the box might also insulate its own interior, and thus throw the readings off. It is a good idea to take a few sample readings of the interior and exterior of the box during the course of first summer and winter, just to make sure that there are no substantial temperature differences.

Hygrometer
The typical analog hygrometer measures humidity by taking a relative measurement between a dry bulb and a wet bulb thermometer. This instrument should definitely go inside the shelter of the weather station, and not be mounted on the outside walls or top.

Sources: www.bbc.co.uk/wear/weather/wind_vane.shtml; weatherstations.lifetips.com/cat/61724/setting-up-a-weather-station.html; www.usd116.org/ums/apple/service/recycle/terencedavid2.htm