Frog too early...Help

You can put the frog outside and the sooner the better.
The cold weather will cause him to go into a state of
hibernation, he'll be fine. They will wake up in warm
times, even if they are out of season, and then go back
into hiberation. They are totally temperature driven.

If you want to keep it as a pet until the weather really
gets nice you can feed it crickets from the pet store.