My broody hen has been sitting on her eggs for 17 days....The temperature has been hot, and the humidity quite warm for a good period of that time. I was wondering...will that affect the hatch time at all?
We have a hen that has done this every year in the spring. Our springs are very warm and sometimes quite rainy. In watching her, she seemed to have kept the humidity control to her liking by either squashing down very low on her eggs, or even slightly standing up. Each time she went 21 days--except one time she went 20 and a half.
I don't know how it will turn out for you, but that is what our experience has been a few years in a row.
I LOVE my broody. She has a retirement plan with me. For me it sure beats using an incubator.
Hatch time can be affected by temperature, if it's too hot, the chicks may hatch a day early, too cool, they will hatch late. Hens are pretty good at controlling the environment they brood their eggs in, they constantly shift and roll and rearrange their eggs to ensure they are o.k. I've had broody hens hatch eggs fine and on time in all sorts of weather conditions and all 4 seasons, from freezing cold winters to hot as hades summers. (I raised chickens in South Africa for a few years.)