Humidity Levels in Illinois During December

The average humidity in December is listed below for places in Illinois. The tables give daily averages along with highest and lowest relative humidity levels.

Relative humidity measures the actual amount of moisture in the air as a percentage of the maximum amount of moisture the air can hold.

All the numbers here are averages for the years 1961 to 1990.

Average Humidity

In this table, the Daily number is the average of humidity readings taken every three hours throughout the day. Morning percentages are for 6 am and Afternoon measures are for 3 pm local standard time.

Average relative humidity (%) in December
Daily Place Morning Afternoon
76 Chicago 80 68
74 Moline 78 67
78 Peoria 83 70
78 Rockford 82 70
78 Springfield 83 70

Highest and Lowest Humidity

Below are the averages during December for maximum and minimum humidity levels in Illinois. The hours when this month's highest and lowest humidity readings usually occur are given in local standard time.

Daily high and low relative humidity (%) averages in December
High Time Place Low Time
79.8 6 am Chicago 67.9 3 pm
78.3 6 am Moline 66.7 3 pm
82.9 6 am Peoria 69.6 3 pm
82.4 6 am Rockford 69.8 3 pm
82.6 6 am Springfield 69.7 3 pm

World Data Center for Meteorology. Climate of the World.

Illinois Humidity
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