At the fly-in I visited yesterday, few of the planes could even carry enough fuel to "go around", let alone go over Most would just have to stay home......
Flying back to Seattle from a Boeing assignment in Pa. in 1964 I was on a 707-320, NWA. We encountered a front over Wyoming exactly where Jim has posted the cells at 45K. The pilot flew the north trying to find a break in the wall of clouds then did the same thing flying south and found one . On the way through we could see that the clouds were still topping out way above us. There was another bank ahead and he had to turn south and he flew for a long time in an active and threatening canyon. When it got thinner I could see through a break and saw a huge patch of a field covered with parked airplanes. The only thing that I could think of was Davis-Monthan. Anyway, we started to fly north-northwest and arrived in Seattle 1 hour late. That was the biggest pile of clouds that I have ever seen.