At what temperature would you say is ok for a beardie to be outside to bask in the sun? It's not exactly warm where I am now (concord, New Hampshire) but it's pretty nice directly in the sun. He's only 4 months and hasn't been able to go outside yet
I usually bring them out if it's above 70. If it's really sunny out then 60s is OK for a while too. When they darken and start basking their skin temps can be way higher than the ambient temps and they do pretty well.
Too cold or they are just darkening to improve basking efficiency. When they've had enough their color will lighten quite a bit to start to reflect heat/light.