Occasionally you will run across the term “AUTO” in an Aviation Routine Weather Report (METAR). What does it mean, but more importantly, is this relevant to you as a pilot?

The absence or presence of “AUTO” helps pilots make more informed weather decisions.

What does AUTO mean in the METAR?

A weather report without human supervision will say “AUTO.”

When a human (ie. ATC) interacts or supervises the weather reporting system, the AUTO will disappear from the METAR.

Let’s dig a little deeper though because in order to know whether an airport will have AUTO in it’s METAR, you must understand where your weather reports come from.

Weather reports come from ASOS or AWOS stations. Some ASOS stations take it a step further and produce an ATIS.

For example, check out these different airports in Oregon:

Here are the same airports with the types of weather reporting stations:

The ATIS and ASOS stations both have an operating tower (with a real human) but KCVO does not have a tower, which is why you see “AUTO.

Pilots can find out the different reporting stations in their State by going to this FAA website: Surface Weather Observation Stations

There is an exception to the rule that towers always monitor the METAR and that is when a tower shuts down at night.

At night the system will lose its human interaction (because the tower people go home) and the METAR will say AUTO. So, during the day, you won’t see AUTO, but then at night, you will see a METAR with AUTO in it.

Most of the time AWOS systems will not have any human interactions. You will usually find AWOS systems at nontowered airports.

I know the difference between these systems can be a bit confusing, so I wrote a more in-depth article on the difference between AWOS, ASOS, and ATIS. Check out this article for more information:

The Difference Between ATIS, ASOS, and AWOS.

Also, I wrote a more in-depth article about how to read METARs. Click here to get a complete understanding of METARs.

Finally, you can also download a more comprehensive PDF guide to decoding not only METARs, but TAFs and NOTAMs by signing up below.