Mine are 7 weeks. They have been in there coop 3 nights. I have been keeping it no colder than 53. However it is warmer under the light. I am just going off some advice given to me on this site. It seems 50 may be a little cool for that age, but Im not certian. I would try to warm it up a bit. We put a small space heater in our coop as it is still snowing here and getting down in the teens at night.
Chicks need to be at 95 the first week, then 90, 85 and 80 the 4th week. So unless they have a light that will make it 80 degrees under it, then I'd say no.
I have 3, 5 week old birds in my den because it is still getting down in the 40's at night and only the 50's during the day....
I would say no unless you have a heat lamp in your coop. They don't have all thier feathers yet.
Chicks are not feathered with mature feathers to retain heat and regulate body temps until 8 - 10 weeks. Some breeds need 12 weeks. Without a lamp those chicks will suffer from the cold. Remember when a chick gets chilled it has a hard time recovering and it can be fatal.