I am in Maine and we havent had a day it hit 70 yet but I put 2 photoperiods out on the front porch a week or so ago and they are doing great so far. I think the lows have been in the high 40's but they are close to the house so they get some residual heat. My autos are just seedlings but I plan to kick them out next week. 

The one time I grew Autos inside it seemed like toping them prolonged the time in veg to about 5-6 weeks and I kept feeding grow nutes for a couple of weeks after that and they kept on stretching, that is just a theory and a one time grow so take it for what its worth and remember there is risk. There are lots of auto growers on here and lots of outdoor growers on here, I am neither so wait for them to chime in and good luck