Well, it is kind of difficult to know if the weather has had any effect on the hens without knowing what they are experiencing. The only Cullman location that Wikipedia shows is in Alabama.
The weather service shows that this part of the country has been experiencing afternoons with the temperature up around 60°F and the thermometer dropping to about 30° or 32° on half the days so far this month. With some wind and rain, I don't think that the birds should be sleeping outdoors. However, the cold is probably not putting much stress on them.
Right now, your sunrise is about 7am and the sunset is about 5pm. With only 10 hours of daylight, they are really going to feel the effects of reduced light. It probably wouldn't make much difference if the hens were young but you have made it sound like they have gone thru at least 1 winter.
If I'm understanding your weather correctly, I don't really think that the cold is having much of an effect on them. They are well insulated critters and if they are staying dry and out of drafts, they can just increase their feed intake to pick up some more calories.
Steve