Definition
An in-flight weather advisory issued by the National Weather Service to alert pilots — particularly those flying light aircraft or operating without significant instrument capability — of weather conditions that may affect aircraft safety but are less severe than those covered by a SIGMET. AIRMETs cover moderate icing, moderate turbulence, sustained surface winds of 30 knots or greater, widespread areas of ceilings less than 1,000 feet and/or visibility less than 3 miles, and extensive mountain obscurement.
Plain English
A weather warning for pilots about conditions that are bad enough to matter, but not extreme. Things like moderate ice on the wings, bumpy air, strong surface winds, low cloud, or poor visibility — the kind of weather that can make a flight in a small plane uncomfortable or unsafe.
Context Anchor
Pilots see AIRMETs during preflight weather briefings, in aviation weather products, and in flight-planning apps before deciding whether a route is safe and practical.
Derivation
From 'airmen' (pilots and crew) plus 'meteorological' (relating to weather). The name simply states what it is: weather information for airmen. Knowing this helps you remember it is a pilot-focused weather product, not a general forecast.
Why Pilots Care
Pilots review AIRMETs to decide whether to delay, reroute, or change altitude so they avoid conditions that could reduce safety margins in light aircraft.
Grounding Statement
If an AIRMET covers your route, the weather may still be flyable, but it deserves a careful look before you launch or continue.
Intuition Check
Do not read AIRMET as a routine weather forecast. It is an advisory that points out weather conditions that could affect flight safety over a broad area.
Example Sentence 1
During the preflight briefing, the pilot noted an AIRMET for moderate icing between 6,000 and 12,000 feet and chose to file a route at a lower altitude.
Example Sentence 2
An AIRMET for IFR conditions was active along the coastal route, so the VFR-only pilot filed an alternate inland path.