Odd, but in twenty-some years of MOA membership and lots of rallies I can't remember anyone ever complaining about it being COLD, but it seems like no matter where the rally is sited there's gonna be some bitchin' 'bout the HEAT. It's July, what do people expect?? MSP will be great this summer, and while yes, it can be hot and/or humid there, if you want to cool down you have lots of options--say a ride down south on the River Parkway or a side trip to Duluth for Aerostitch or Dylan fans. Or, you can do what I do and rotate between the shaded beer tent and the air-conditioned vendor areas. But taking a ride to cool off is usually a lot cheaper....
Billings will be great too, as there are all kinds of scenic day trips from there--including the Big Horn Mountains, where you can climb to almost 10k ft on some of the best curvy asphalt in the west. Lots of interesting sites to see, like the Big Horn Battlefield and more. It's all good, and I plan on being at both rallies but for now, the focus is on gearing up for Minneapolis.