Automatic terminal information service, or ATIS, is a continuous broadcast of recorded aeronautical information in busier terminal areas. ATIS broadcasts contain essential information, such as current weather information, active runways, available approaches, and any other information required by the pilots, such as important NOTAMs. Pilots usually listen to an available ATIS broadcast before contacting the local control unit, which reduces the controllers' workload and relieves frequency congestion. ATIS was developed and adopted by the FAA in the mid-1960s and internationally (under the direction of ICAO) beginning in 1974. Before the adoption of ATIS, this information was routinely disseminated to each aircraft separately, increasing controller workload during periods of high traffic density.

In the U.S., ATIS will include (in this order): the airport or facility name; a phonetic letter code; time of the latest weather observation in UTC; weather information, consisting of wind direction and velocity, visibility, obstructions to vision, sky condition, temperature, dew point, altimeter setting, density altitude advisory if appropriate; and other pertinent remarks, including runway in use. If it exists, the weather observation includes remarks of lightning, cumulonimbus, and towering cumulus clouds. Additionally, ATIS may contain man-portable air-defense systems (MANPADS) alert and advisory, reported unauthorized laser …

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