Definition
The Runway Visual Range (RVR) reading taken from a transmissometer or visibility sensor located near the midpoint of the runway. It reports the horizontal distance, in feet, that a pilot should be able to see down the runway from that midfield position.
Plain English
It is the visibility measurement taken from the middle of the runway, telling pilots how far they can see along the runway from that point.
Context Anchor
You may see Mid RVR in low-visibility weather reports, instrument approach information, or runway condition reports when more than one RVR value is given for the same runway.
Derivation
RVR stands for Runway Visual Range. 'Mid' simply indicates the sensor's position — partway down the runway — distinguishing it from the Touchdown RVR (near the approach end) and Rollout RVR (near the departure end).
Why Pilots Care
Affects whether landing or takeoff minima are met when the midpoint visibility differs from the touchdown reading.
Intuition Check
“Mid” does not mean the middle of the approach or the middle of the flight. Here it means the RVR equipment near the middle of the runway.
Example Sentence 1
The ATIS reported Touchdown RVR 2400, Mid RVR 1800, and Rollout RVR 2000.
Example Sentence 2
With touchdown RVR at 1400 feet and mid RVR at 900 feet, the approach remained within limits.