You didn't say where you were from but I hunt a lot of squirrels in northern MN. As you know squirrels don't hibernate. They do however sleep through long spells of bad weather. We had one of the longest stretches of sub zero weather this winter and I expected them to come out looking sort of poor. Not the case, they were plump and in no hurry to get to the dinner table. Don't expect the first day or so of warm weather to get them moving and a cold stretch broken by warmer weather but no sun or with a storm just makes them roll over and go back to sleep. Keep an eye on the bird feeder, they sure like those sunflower seeds and when you see more than one they will most all be up and moving about. Around here 10 degrees is a little cold for them, the upper teens is about what it takes. Sunshine makes a big difference but not around Christmas when it is low on the horizon. Hope this helps, It may be much different in other places but you can count on the trick of watching for them around the feeder.