[ThePythonicCow]

And all those radars are set up the same way

Well, I suppose so, yes. Most radars sit on the ground (disregarding the non-stationary ones on aircraft and ships, of course.) And if you're running a radar on the ground to see what's in the sky around you, you kinda have to angle it up into the sky, but not too steep, or you won't see anything except what's right above you.

[Judith Anne]

Okay. I just have never seen anything like this in my four years of looking at the radar maps. A first time for everything.....

[Judith Anne]

Oh, anyway, I was referring to the gain, mentioned by HAL9000 in post 4, all being set up the same to get this effect, not necessarily the angles...