You are in for a hard and long road to success! Believe me it isn't easy.. It's just as hard on us as it is on them to stand out in the cold all hours of the day and night waiting, waiting, waiting for this little critter to go potty so that you can rush back into the warm and toasty house.
It's much easier to train in the warmer months but still very doable in the cold months. Dont expect miracles to happen over night. Consistent and routine trips outdoors is what it will take to get him to go. If you dont they will pee and poo in the house and it becomes a big problem and habit to break the longer you let it continue. You may want to get a coat to keep him warm and even some small treats to reward him after each successful trip.
I had two that had to be trained during winter months, but I also paper trained them. Which allowed them to potty on the papers when refusing to go outside. (but I still kept to the routine schedule) It was something that I knew was going to happen so I didn't get to frustrated or upset over it. It's bound to happen!
I would continue to have regular and routine trips outside after meals, when they wake up during the nightly or naps and throughout the day as you would normally. But keep you papers/pads available (close to the door) for those stubborn times.
Tip: try taking a poo from when they went indoors, outside in the yard area that you want them to use. Than when you take them out, take them to that spot every time.
Take a look at my training techniques on my site: wish you luck!
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