When you gotta' play, you gotta' play!
Here in Chicago, low 40's to high 30's if the wind lies down. A little bit of Sun doesn't hurt. I've already played in low 40's this fall. It sucked, but not as much as not playing.
I have a buddy who's crazy about platform(?) tennis. They'll play while sporting snotcycles.
Remember this, you are lucky to have lived during the golden age of beer (except Guinness, Heineken and Sam Adams).