Definition
A three- or four-letter code assigned to a specific airport or weather reporting location, used to label that station in aviation weather reports, forecasts, and charts. In the contiguous United States, station identifiers are typically four letters beginning with K (for example, KORD for Chicago O'Hare).
Plain English
A short letter code that names the airport or location a weather report came from.
Context Anchor
Seen near the beginning of aviation surface weather reports, such as METAR and SPECI reports, immediately after the report type.
Derivation
‘Station’ comes from the Latin statio, meaning a fixed place or post. A weather ‘station’ is a fixed reporting site, and the identifier is its short name.
Why Pilots Care
Knowing the station identifier tells the pilot exactly where the reported weather conditions apply so they can decide whether conditions are suitable for their route.
Intuition Check
Do not read station identifier as a general name for the airport. In weather reports, it means the specific coded location of the reporting station.
Example Sentence 1
The METAR began with the station identifier KSFO, confirming the report was for San Francisco International.
Example Sentence 2
Different airports have different station identifiers even when they are close to each other.