Slide 91 of 95
Surface weather observations, both human and automated, provide ground-truth information to assist in interpreting satellite and radar information. Forecasters are able to monitor precipitation rates, temperature, pressure, and wind changes.
Photograph of Automated Surface observing System (ASOS) equipment. (NOAA/NWS)
-Upper right: Hygrometer, which measures humidity; barometer, which measures atmospheric pressure; and thermometer, which measures temperature.
-Upper left: Transmissometer, which measures visibility.
-Lower right: Anemometer, which measures wind speed and direction.
-Lower left: Laser ceiliometer, which measures cloud heights and amounts.