Chatham, Illinois gets 38 inches of rain, on average, per year. The US average is 38 inches of rain per year.
Chatham averages 19 inches of snow per year. The US average is 28 inches of snow per year.
On average, there are 201 sunny days per year in Chatham. The US average is 205 sunny days.
Chatham gets some kind of precipitation, on average, 101 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 86 degrees
Winter Low: the January low is 18
Rain: averages 38 inches of rain a year
Snow: averages 19 inches of snow a year
BESTPLACES COMFORT INDEX
The annual BestPlaces Comfort Index for Chatham is 7.2 (10=best), which means it is one of the most pleasant places in Illinois.
8.4 / 5.3
Summer / Winter
September, June and May are the most pleasant months in Chatham, while January and December are the least comfortable months.