Definition
In a METAR, AUTO is a report modifier indicating the observation was generated entirely by an automated weather station, without human augmentation or correction. It appears immediately after the date/time group when applicable.
Plain English
AUTO in a weather report tells you the report was put together by a machine, not a person. No human checked or added to it.
Context Anchor
Seen near the beginning of a METAR, the routine aviation weather report pilots use before and during flight planning.
Derivation
AUTO comes from the Greek autos, meaning “self.” In this weather-report context, it points to self-operating equipment: the station reports the weather without a human observer.
Why Pilots Care
Pilots know automated reports can miss or misreport certain details such as visibility, cloud layers, or present weather that a human would observe.
Intuition Check
AUTO does not mean the airport, runway, or flight is automatic. In a METAR, it only tells you how the weather report was made: by equipment, not by a human observer.
Example Sentence 1
The METAR showed AUTO after the time group, so the pilot knew the cloud and weather information came from sensors rather than an observer.
Example Sentence 2
Seeing AUTO in the report, the pilot reviewed the remarks section for any sensor limitations before deciding on an approach.