Good strain for cold climats?

Im planning my second grow this summer and i want to go with lowrider diesel and a regular strain but im having trouble finding one that will finish on time. I live in the montreal area so pretty much first frost is around end of september. I want a mostly indica strain with a good yield and better than average potency. Im ordering the seeds off attitude. Anyone got suggestions?

"guerillagold"

this is im told the most potent autoflowering strain that was made for outside