Humidity Levels in Illinois During May

The average humidity in May 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 May
Daily Place Morning Afternoon
64 Chicago 77 51
65 Moline 79 49
66 Peoria 80 52
65 Rockford 80 50
66 Springfield 80 51

Highest and Lowest Humidity

Below are the averages during May 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 May
High Time Place Low Time
77.4 3 am Chicago 51.0 3 pm
79.4 6 am Moline 49.3 3 pm
80.3 6 am Peoria 52.0 3 pm
80.0 6 am Rockford 49.5 3 pm
80.0 6 am Springfield 50.8 3 pm
Reference

World Data Center for Meteorology. Climate of the World.

Illinois Humidity
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