The climate in Grafton, IL is moderate and comfortable throughout the year. During the summer months, temperatures tend to stay in the mid-80s with high humidity levels. In the winter, temperatures can drop into the 20s and snow is common. Grafton also experiences strong thunderstorms during certain times of the year, especially during spring and summer. The climate in this area of Illinois can be unpredictable at times but generally remains warm and comfortable throughout much of the year.
Grafton, Illinois gets 41 inches of rain, on average, per year. The US average is 38 inches of rain per year.
Grafton averages 14 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 Grafton. The US average is 205 sunny days.
Grafton gets some kind of precipitation, on average, 96 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 88 degrees
Winter Low: the January low is 21
Rain: averages 41 inches of rain a year
Snow: averages 14 inches of snow a year