What age can my chicks stay outside overnite

Mine are 4 weeks old and last night was thier first night spent in the coop!
(they did better than I did)-lol
Today they are HAPPY GIRLS!!!
We live in NJ and our night time temps are about the same. Tonight I think it's suppose to be around 59- 60 degrees.
Just in case I did leave a lamp w/ a 60 watt bulb in there. But when I peeked in to check on the kids-(lol) They had gone to roost.

 

I have 2 silkies that have been outside in the dog run since they were 3 weeks old. They sleep in a large kitty litter lid filled with hay. I live in Ocala so the weather is fine for them to be outside right now.

 

My babes are 4 weeks and they've been out for 2 nights now. I'm in central NC and it's 95 during the day and very humid so at night when it's about 60-65 they love it. I think yours would be fine outside at night.

 

My youngest are just now 3 weeks old and they've been in the coop with the 'older chicks' for almost a week. Our night time temps are about the same as yours now, and they've been just fine and happily roost at night and free range with the 'big birds' all day.

 

I'm still waiting out here as it's still in the 40's at night. I put mine out in the morning with these temps. and so she is getting used to cool, but it warms up quick. I am guessing she is about 4 weeks old right now. She is getting so tame. When I call her to come in at night she comes right to me now and hops right up in my hand. I have to be careful cause she wants to jump on my shoulder. I'm afraid she might fall off and a dog might grab her.

 

Maybe I'm crazy, but I put 4, 5 and 6 week olds into the coop at high 20's, low 30's at night. They had a very snug coop, 100w lamp, and plenty of shavings and bedding straw. They did great from the start and never seemed to worry about it. The youngest two refused to leave the coop until 10am most mornings, but the oldest were out with frost on the ground even at 6 weeks old. They were far more resilient than I thought!

-MTchick