St. Clair County, Illinois gets 42 inches of rain, on average, per year. The US average is 38 inches of rain per year.
St. Clair County averages 13 inches of snow per year. The US average is 28 inches of snow per year.
On average, there are 202 sunny days per year in St. Clair County. The US average is 205 sunny days.
St. Clair County gets some kind of precipitation, on average, 99 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.
Summer High: the July high is around 89 degrees
Winter Low: the January low is 22
Rain: averages 42 inches of rain a year
Snow: averages 13 inches of snow a year
BESTPLACES COMFORT INDEX
The annual BestPlaces Comfort Index for St. Clair County is 7.2 (10=best), which means it is one of the most pleasant places in Illinois.
7.4 / 5.7
Summer / Winter
September, May and October are the most pleasant months in St. Clair County, while January and December are the least comfortable months.