Morrison, IL, gets 36 inches of rain per year. The US average is 37. Snowfall is 31 inches. The average US city gets 25 inches of snow per year. The number of days with any measurable precipitation is 105.

On average, there are 196 sunny days per year in Morrison, IL. The July high is around 86 °F. The January low is 12 °F. Our comfort index, which is based on humidity during the hot months, is a 45 out of 100, where higher is more comfortable. The US average on the comfort index is 44.

In recent years, average temperatures in the county seat of Morrison have ranged from a low of 10 °F in January to a high of 85 °F in July, although a record low of −30 °F was recorded in February 1905 and a record high of 112 °F was recorded in July 1936. Average monthly precipitation ranged from 1.51 inches in February to 4.69 inches in August.