Definition
A category of weather conditions defined by a ceiling between 1,000 and 3,000 feet AGL and/or visibility between 3 and 5 statute miles inclusive. MVFR conditions are legal for VFR flight but represent reduced visibility and lower clouds than standard VFR, requiring extra caution and good judgment from the pilot.
Plain English
The weather is good enough to fly under visual rules, but only just. The clouds are lower and you can't see as far as you'd like, so you have to be more careful.
Context Anchor
Seen on weather depiction charts, airport weather reports, and aviation forecasts as a quick label for how good or poor the flying weather is.
Derivation
Marginal comes from the Latin margo, meaning 'edge' or 'border.' MVFR weather sits on the edge between full VFR conditions and instrument conditions — close to the line, but not over it.
Why Pilots Care
Signals that VFR flight is possible but requires heightened attention to terrain, obstacles, and changing conditions.
Grounding Statement
Picture a low gray cloud layer and only a few miles of forward view; that is the kind of reduced visual environment MVFR is pointing to.
Intuition Check
MVFR does not mean visual flight is automatically illegal. It means the reported weather is near the lower end of visual flying conditions.
Example Sentence 1
The briefer reported MVFR conditions along the route, with ceilings around 2,000 feet and visibility of 4 miles.
Example Sentence 2
Checking the weather depiction chart, I saw MVFR across the mountains and decided to file an IFR flight plan instead.