While the summer makes people think about going solar, the truth is that the cooler temperature of winter can allow your panels to produce more energy than during summertime. Of course if you have snow pile on your panels you might see a different effect.
Why do solar panels work better in cold weather?
If the temperature gets too hot, your solar panels will actually under-perform. The ideal testing conditions for solar panels under STC is done at 25°C, and any higher than that and the efficiency of the modules goes down. You can learn more about the ideal temperature for solar panels here, but the general idea is that if your panels remain at or under 25°C (77°F), they will be able to produce more energy.