I bet some of us got this wrong.

Not many might know what the Stevenson screen is used for. It is a special enclosure which shields meteorological instruments against precipitation and direct heat radiation from outside sources. The Stevenson screen doesn't influence the results, as it still allows air to circulate freely around the instruments. The Stevenson screen holds instruments that may include thermometers (ordinary, maximum/minimum), a hygrometer, a psychrometer, a dewcell, a barometer and a thermograph. Its purpose is to provide a standardised environment in which to measure temperature, humidity, dew point and atmospheric pressure.

The device is also known as instrument shelter. It was named after Thomas Stevenson, a British civil engineer, who designed the screen in the late 19th century.