Tower visibility is determined from which location when surface visibility is from another location?

Tower visibility refers to the visibility conditions as reported by the control tower at an airport. Even if surface visibility is measured at a different location, the control tower has specific instruments and vantage points that are used to assess visibility conditions relevant to aircraft operations.

The control tower's visibility measurements are especially critical in ensuring that pilots have the necessary information when making decisions about landing and takeoff, as weather conditions can vary significantly across different parts of an airport. Therefore, the visibility reported by the control tower acts as the authoritative source for pilots and air traffic controllers, focusing primarily on operational safety around the airport.

While other locations like ground level or the runway threshold may offer visibility assessments of their own, it is the control tower that provides the key visibility reporting necessary to inform air traffic operations comprehensively.