A twisted limb can be fixed pretty easily by twisting and holding opposite of the twist. Go slow and repeat the process for as amny times as it takes to get it straight...if it returns, repeat. You can also use hot water to warm the limb and then do the same...use water to warm, twist opposite, then run under cold water...repeat if/when necessary. (Don't use anything else to heat the limb, just hot water).
I'd use more caution here though...I've untwisted many bows, but most were oldies that took this kind of set or twist over time...sounds like the weather and the bow possibly being strung caused the limb to twist in this case...take extra care, go a bit slower and use caution when stringing and drawing.