St. Charles, IL has a humid continental climate with four distinct seasons. Summers are warm and humid, while winters are cold and snowy. Spring and fall are mild but can be unpredictable, with temperatures ranging from hot to cold depending on the time of year. Rainfall is moderate throughout the year, with an average of 36 inches of precipitation annually. Snowfall averages around 25 inches per year in this part of Illinois. Average temperatures range from a low of 20°F in January to a high of 82°F during the summer months.
St. Charles, Illinois gets 38 inches of rain, on average, per year. The US average is 38 inches of rain per year.
St. Charles averages 30 inches of snow per year. The US average is 28 inches of snow per year.
On average, there are 189 sunny days per year in St. Charles. The US average is 205 sunny days.
St. Charles gets some kind of precipitation, on average, 120 days per year. Precipitation is rain, snow, sleet, or hail that falls to the ground. In order for precipitation to be counted you have to get at least .01 inches on the ground to measure.
Weather Highlights
Summer High: the July high is around 85 degrees
Winter Low: the January low is 15
Rain: averages 38 inches of rain a year
Snow: averages 30 inches of snow a year