I am in the same location. It wasn't due to wind, 58 just comes in a little weaker than the rest. I can get it stronger by moving the antenna around but then I lose signal on the other stations. As long as I can get it at about 72% then I am fine. I do have problems with my 811 in the other room, constantly have to move the antenna for signal, might have to do with a picky tuner in it.
It was actually Ch. 13 that I was unable to pull in at all. Have not checked it yet today. But I am not overly concerned since Ch. 13 HD is part of the DISH local package. It's HD local Chs. 6 and 40 that I want to be sure and get OTA since they are not carried by DISH.