Planning for the weather is an important factor for making your trip to Schaumburg a success, especially when you’re splurging. The hottest months are usually July and August with an average temp of 70°F, while the coldest months are January and February with an average of 29°F. The snowiest months in Schaumburg are January, March, November, and February, with each month seeing an average of 5 inches of snowfall.