You might spend a lot of your holiday inside, but if you want to see more of the area, looking at local weather trends is a good idea. The hottest months are usually July and August, with an average temperature of 20°C, while the coldest months are January and February, with an average of -4°C. The snowiest months in Madison are January, December, March and November, with each month seeing an average of 22 cm of snowfall.