Marietta, IL has a temperate climate with an average temperature of 45.4 degrees Fahrenheit throughout the year. The summers tend to be hot and humid with temperatures often exceeding 80 degrees Fahrenheit. Winters are generally cold and snowy, with temperatures rarely dropping below 25 degrees Fahrenheit. The area receives an average of 34 inches of rain per year, primarily during the spring and summer months. During winter months, snowfall averages 10 inches per year. In addition, Marietta is known for its high winds which can cause problems in the winter months when traveling on roads or running outdoor activities.
Marietta, Illinois gets 38 inches of rain, on average, per year. The US average is 38 inches of rain per year.
Marietta averages 19 inches of snow per year. The US average is 28 inches of snow per year.
On average, there are 193 sunny days per year in Marietta. The US average is 205 sunny days.
Marietta gets some kind of precipitation, on average, 93 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 86 degrees
Winter Low: the January low is 15
Rain: averages 38 inches of rain a year
Snow: averages 19 inches of snow a year