Definition
Prevailing horizontal visibility near the earth's surface as reported by the United States National Weather Service or an accredited observer. It is the official visibility figure used to determine whether weather minimums for takeoff, landing, and certain operations are met.
Plain English
How far someone standing on the ground at an airport can see horizontally, as officially reported by a weather observer.
Context Anchor
Seen in airport weather reports, weather briefings, and visibility minimums for visual flight.
Derivation
Ground comes from an old word meaning the earth or surface. Visibility comes from words meaning able to be seen. Together, they point to visibility judged from the surface, not from the aircraft.
Why Pilots Care
It is the official visibility value used to decide whether visual flight rules are permitted from the surface and to determine if takeoff or landing minimums are met.
Grounding Statement
Picture someone standing at the airport and reporting how far they can see along the surface.
Intuition Check
Ground visibility does not mean how well you can see the ground from the airplane. It means how far visibility extends near the ground from an official ground observation.
Example Sentence 1
The tower reported ground visibility of three miles, so the pilot was clear to begin the approach.
Example Sentence 2
Fog reduced ground visibility to one mile, so the pilot elected to wait for improvement before takeoff.