Annual Average Humidity in Oregon

The average humidity year round is listed below for places in Oregon. 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 7 am and Afternoon measures are for 4 pm local standard time.

Average yearly relative humidity (%)
Daily Place Morning Afternoon
81 Astoria 87 72
78 Eugene 88 60
68 Medford 82 47
58 Pendleton 67 47
73 Portland 84 59
75 Salem 85 59

Highest and Lowest Humidity

Below are averages over the year for maximum and minimum humidity levels in Oregon. The hours when the highest and lowest humidity readings usually occur are given in local standard time.

Annual averages for daily high and low relative humidity (%)
High Time Place Low Time
88.2 4 am Astoria 71.6 1 pm
90.3 4 am Eugene 60.1 4 pm
83.6 4 am Medford 47.1 4 pm
68.9 4 am Pendleton 47.0 4 pm
84.8 4 am Portland 58.6 4 pm
87.6 4 am Salem 58.9 4 pm
Reference

World Data Center for Meteorology. Climate of the World.

Oregon Humidity
Back to Top