You should be fine with summer tires. Below 40 is dicey, but you will really notice below freezing Here in Michigan it became unseasonably cold these past two Novembers and I don't change to my winter tires until Thanksgiving. I spent both Novembers on summers and you just have to be careful around freezing as dry pavement will seem like driving on ice !
For my summer tires I like to stay around a 200 treadware, like my Hankook RS3s, and I was going to try BFG Rivals this time around .
Due to considering selling the car and needing some tires that would last at least 10k, I considered Hankook V12 Evos, which I've had before They are an excellent summer tire with about 85-90% of the capability of the RS3-RS4.
I instead went with the G-Force Comp 2. I was pleasantly surprised They are as good as the V12 Evo, and did well in a couple of track events. I would recommend them (the summer tire, not the a/s)