Chickens naturally slow their egg production in the winter. Many folks follow that up by mistakenly believing it has something to do with cold temperatures. In reality, it's the shortened daylight that causes chickens to lay less frequently.
Our weather right now is good proof of this. Our mid-October days are shortening even though our temperatures have remained relatively warm. Still our gals are pretending it's time to buckle down for winter and turn off their laying machines. Egg production has dropped off tremendously. I decided it was time to put a low-wattage bulb in the hen house.
This allows us to extend their light exposure, fooling them into believing the days are longer than they actually are. When it actually gets cooler, I can switch the bulb out for a higher wattage to keep the gals warm throughout the winter.