Ben Hallert wrote:

snip
They can only really be accurate out to about 6
miles. A human with a Mark I Eyeball could pick a landmark furthre
away and provide a bigger distance, but for all intents and purposes,
the max visibility will be defined by the technical limitations of the
available data sources.

Since the source of a pirep is a pilot, not an automated weather station,
and the main recipient of a pirep is a pilot, not an automated weather
station, visibility should be reported as an estimation in the pilot's
opinion much greater than that which is artificially restricted by
automation.

In any event, I did call Buffalo FSS late last night to ask the specialist
about this and in his opinion the Cleveland specialist was incorrect.
Report visibility in the distance we see, were his words.

Again, had I been a low time VFR pilot launching on a cross country, I
certainly would want to know about haze limiting visibility, for even 10
miles and haze will appear much lower as the sun draws closer to the
horizon.

--
Peter