ATIS (Automated Terminal Information Service) is a continuous broadcast of recorded non-control information. ATIS broadcasts contain essential information, such as weather information, which runways are active, available approaches, and any other information required by the flight crew.

Pilots usually listen to an available ATIS broadcast before contacting the local control tower, in order to reduce the controllers' workload and relieve frequency congestion.

The recording is updated when there is a significant change in the information, like a change in the active runway. It is given a letter designation (e.g. bravo), from the Phonetic Alphabet. The letter progresses down the alphabet and starts at Alpha each day. When contacting the control tower or ground station, a pilot will indicate he/she has "information" and the ATIS identification letter to let the controller know that the pilot is up to date with all current information.

As a support to the ATIS audio broadcast you also have some text and graphical display options such METAR, DECODED METAR, NOTAMs, RADAR PICTTURES and AIPORT DIAGRAM. All these information give you an extensive
brief for the local weather and other non-control information.

When the Tower is closed (11 PM to 6 AM) the local ASOS information is broadcasted over the 134.5 frequency. This weather observation is updated continuously and might slightly differ from the METAR which is updated by the hour.