What is an AIRMET?

• A. A weather advisory for severe weather affecting only a small area.
• B. A report of routine weather from METAR.
• C. An AIRMET is a weather advisory for less severe phenomena affecting larger areas and general aviation; SIGMETs are more severe and urgent.
• D. A notice for wind calm conditions.

Answer: (C)

An AIRMET is a weather advisory for less severe phenomena that can affect flight over a broad area, with pilots in general aviation and those operating under VFR often watching them. They’re meant to flag conditions that aren’t extreme but still matter for safety, such as moderate icing, moderate turbulence, or situations like mountain obscuration that reduce visibility or ceiling. AIRMETs cover larger regions and are less urgent than SIGMETs, which warn about more significant and urgent weather hazards.

So this description matches the idea that an AIRMET is a weather advisory for milder phenomena affecting larger areas and general aviation, while SIGMETs are the more severe and urgent alerts.

The other options don’t fit because an AIRMET isn’t a routine METAR report, isn’t specifically about wind calm conditions, and isn’t limited to a small area or severe weather—AIRMETs target broader areas with less severe conditions.