Mission is in the sub-tropics zone, and fortunately that generally means some sun and warmth! Put in the mix palm trees and blooming butterfly plants, and the Valley offers you a nice November getaway.
The mean temperature during the Festival is in the 70s. However, mornings can be cool (50s) and afternoons can be hot (80s +). So, the best clothing strategy: layers, with warm weather layer on bottom. That way you can peel off and adjust as the thermometer rises through the course of the day. Don’t forget a rain jacket, just in case, and a hat for sun. Mosquito repellant suggested.