Mild weather would be a niiiiice change. I'm not counting on it though. Over the years, my 'roo crew has gotten very good at baring the heat. This year my 'roo crew has almost doubled in size, with many first timers. If the heat held off that would be great, but I'm certainly not going to count on it this far out. It IS Bonnaroo... so I can't really imagine it without the sweat and the heat, but I'm sure I could get used to it!
But I'd like to keep the rain at a refreshing and nondestructive minimum.
Ok, so looking at the graph below and looking back to what they had before, accuweather just puts the average temps in as the low and high until it gets 7 days out. Considering a giant heat wave (90+ in IL) is supposedly coming this weekend, I do not believe a word that forecast says.
I've seen the weather change drastically even from 2 weeks out. Best is watch weather channel with overall weather patterns and look at a local 10 day forecast.
As for past year, 09 was fun a bit scary thanks to my friend who put up a solid tent no leaks. Super comfortable the rest of the weekend. In 2010 I was hotter than hades. So somewhere in between would be great weather gods
I am by no means a meteorologist, but I have had an opportunity to review the historical weather data and have consulted with some fellow non-meteorologists. Our prediction is that there is 90% chance of weather all weekend.