I'm having trouble figuring out what "visibility" means. Take today for an example. There were puffy white clouds, not high, but definitely not low, with plenty of bright blue sky above them. I phoned the AWOS and heard that the visibility was ten miles, with scattered clouds at 4,000 feet. That sounded just like what I had seen with my own eyes. The temperature was in the mid-80s and the dewpoint around 60.
But when I got up to about 1,000 feet, I could already see that it was hazy, and at 2,000 there was a definite blueish cast to the ground below. There was no real horizon. The ground just sort of faded away into gray and nothing about 5 or 6 miles away. I flew west to the reservoir, turned, and looked back toward the airport, but couldn't quite tell where it was. I knew where it was, but couldn't see it. So the visibility was a little worse that it had been when I flew to Orange County Airport, the other day.
I'd planned to fly to Petersburg Airport and land, just for the fun of it, but by the time I got to Lake Chesdin, a few miles west of that airport, I could see even less. Rather than keep flying around in a moving circle of five-mile radius, able to see no more than 3 minutes ahead, I decided to turn north again and see if the visibility was any better north of the reservoir. It wasn't. I then got curious about the cloud height, so I climbed toward them. The bases were indeed at 4,000 feet. I climbed on up between the clouds and found that their tops were between 4,500 and 5,000 feet. (It was kind of fun to fly above clouds; student pilots aren't permitted to.)
Well, I couldn't see any better anywhere, so I came back down and turned
back toward the airport. The wind had picked up a bit and was then
030 at 9 gusting 15--so counting the gusts, I had a nice crosswind, about
12 or 13 knots. But landing was fun--an interesting exercise in coordination
now--so I took off and did it again before calling it quits for the day.
So about the visibility: Looking straight up, the visibility
really was pretty good. Even looking horizontally above the clouds,
it wasn't bad, and there was a horizon out there.
Looking toward the ground at almost any altitude, however, the visibility
sucked. So whatever was getting in the way and scattering the light
was evidently down fairly low. I wish now that I'd gone on up three
or four thousand feet above the cloud tops to see how things looked from
there.