What type of weather observation would be recorded by a hygrometer?

A hygrometer is a specialized instrument designed to measure the amount of moisture in the air, which is referred to as humidity. The readings from a hygrometer provide crucial data that helps assess weather conditions, climatic changes, and even indoor air quality. Humidity is a critical aspect of weather observation as it affects temperature perception, cloud formation, and precipitation processes. Therefore, when considering the function of a hygrometer, it is clear that the correct observation it records pertains to the humidity level in the atmosphere.

Other options relate to different meteorological observations: wind speed is measured using an anemometer, precipitation amount is recorded using a rain gauge, and temperature is assessed with a thermometer. Each of these instruments is designed for a specific purpose and provides valuable data to build a complete picture of weather conditions, but when it comes to humidity, the hygrometer is the appropriate instrument.