A weather station is an observation station built for the purpose of obtaining meteorological data. Many stations are equipped with passive sensors such as barometers, thermometers and rainfall gauges to measure various meteorological elements. Some stations are also equipped with instruments to observe soil or surface temperatures at different depths and sea water temperatures.
Wind direction and anemometer generally require little or no ambient obstruction, while temperature and hygrometers require distance from sunlight and radiation sources. Weather buoys and observation vessels at sea can provide additional data such as sea temperature, wave height and tidal cycle.