You'd want your highs in the mid 70's to get normal metabolism out of them, but nighttime temps can drop lower than you think... I currently have all my veileds outside, and our temps range from mid 50's to about 80 degrees (they've been out for a month). I'll keep veileds out up until around 90-95 as long as they have shade to get into, and they can be outside into the low 40's overnight, though I would never recommend it (I've had some overnight lows lower than expected with no ill effects).
it was a good experience for him to be outside i ended up taking a hammper abpout 3 feet tall and 1.5 feet across and sticking a Schefflera arboricola in there with a few 5 ft branches. he loved the sun. i do have a question after i put him back in the cage he climbed on the top screen this happens evrey time i hold him is this just stress or is there something wrong.(i dont hold him much bc he can puncture the skin with his claws)