Definition
Weather conditions expressed in terms of visibility, distance from cloud, and ceiling that meet or exceed the minimums specified for flight under Visual Flight Rules (VFR). When VMC exists, pilots are permitted to navigate and maintain separation from terrain and other aircraft by outside visual reference rather than by sole reference to instruments.
Plain English
Weather that is good enough to fly by looking outside — clear enough air, far enough from clouds, and a high enough cloud base to meet the rules for visual flying.
Context Anchor
You will see VMC in weather, flight planning, and discussions that compare flying by outside visual references with flying mainly by instruments.
Derivation
‘Meteorological’ comes from the Greek meteoron, meaning ‘thing high in the air,’ and refers to the study of atmospheric conditions. So VMC literally describes weather conditions that are good enough for visual flight.
Why Pilots Care
Determines whether a pilot can fly visually or must file an instrument plan, directly affecting route options and safety margins.
Intuition Check
Do not confuse VMC with permission to fly. VMC describes the weather; the pilot must still follow the applicable flight rules, airspace rules, and clearances.
Example Sentence 1
The forecast showed VMC throughout the route, so the pilot filed VFR.
Example Sentence 2
When visibility dropped below the required minimum, the flight could no longer continue in VMC.