One of the worst experiences I have ever had was when I played a festival the first weekend in June a few years back. For the most part, I was playing a vintage Guild 12 string. The weather was in the mid 40's (fahrenheit), misty rain, and wind. You could tune the instruments, and by the end of the song they were out of tune. I resolved to look into the Rainsong guitars (carbon fiber, not a lick of wood in them) as soon as I could. Their tone is pretty good, a little weak on the bass end, and would be much less vulnerable to this and dampness. But I do these gigs so infrequently that I never did.