If both a surface and tower visibility are reported, which value is included in the body of the observation?

When both surface visibility and tower visibility are reported in an observation, the value that is included in the body of the observation is the lower value. This is important because lower visibility conditions are critical for flight operations and safety considerations. Reporting the lower value ensures that pilots and air traffic controllers are aware of the worst-case scenario regarding visibility, which is essential for making informed decisions about takeoff, landing, and navigation.

In aviation weather reporting, it's common practice to emphasize the more restrictive conditions, which in this case would be the lower visibility measurement. This helps to maintain safety standards and ensures that operations are conducted with the utmost caution in potentially hazardous visibility conditions. The other options do not align with standard reporting practices, as reporting higher values or averages could create misleading conditions that could endanger flight safety. Therefore, emphasizing the lower visibility adequately reflects the actual conditions that pilots may encounter.