Humidity Levels in Idaho During September

The average humidity in September is listed below for places in Idaho. 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 at 7 am for Lewiston and 8 am for Boise and Pocatello. Afternoon readings are at 4 pm for Lewiston and 5 pm for Boise and Pocatello, local standard time.

Average relative humidity (%) in September
Daily Place Morning Afternoon
45 Boise 54 29
Lewiston 67 32
47 Pocatello 59 28

Highest and Lowest Humidity

Below are the averages during September for maximum and minimum humidity levels in Idaho. 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 September
High Time Place Low Time
60.0 5 am Boise 28.8 5 pm
68.0 4 am Lewiston 32.2 4 pm
65.4 5 am Pocatello 28.2 5 pm

World Data Center for Meteorology. Climate of the World.

Idaho Humidity
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