Month | Temp. (min) | Temp. (max) | Temp. (avg) | Precipitation |
January | 32°F | 47°F | 38°F | 6.1" |
February | 34°F | 52°F | 42°F | 4.6" |
March | 37°F | 57°F | 46°F | 5.7" |
April | 39°F | 62°F | 50°F | 3.1" |
May | 45°F | 70°F | 57°F | 2.5" |
June | 50°F | 75°F | 62°F | 1.4" |
July | 54°F | 83°F | 68°F | 0.3" |
August | 54°F | 84°F | 68°F | 0.5" |
September | 49°F | 78°F | 62°F | 1.6" |
October | 43°F | 65°F | 53°F | 4.1" |
November | 37°F | 53°F | 45°F | 7.1" |
December | 32°F | 45°F | 38°F | 6.9" |
Index | St. Helens | Oregon | National |
Air quality index | 18 | 32 | 42 |
Pollution index | 3,247,580 | 7,156,356 | 2,726,193 |
Measurement | Total |
Days measured | 360 |
Days with good air quality | 338 |
Days with moderate air quality | 22 |
Days w/ poor A.Q. for sensitive groups | 0 |
Days with unhealthy air quality | 0 |
Pollutant | Total |
Arsenic | 0.002% |
Benzene | 0.020% |
Carbon Tetrachloride | 0.500% |
Lead | 0.040% |
Mercury | 0.001% |
City | Population | Air Quality Index | National Avg. |
Prescott, OR | 85 | 18 | 64.0% |
Kalama, WA | 2,708 | 18 | 64.0% |
Woodland, WA | 6,223 | 18 | 64.0% |
Rainier, OR | 2,080 | 18 | 64.0% |
Columbia City, OR | 1,770 | 18 | 64.0% |
St. Helens, OR | 13,779 | 18 | 64.0% |
City | Population | Air Quality Index | National Avg. |
Lockhart, TX | 13,782 | 44 | 12.0% |
Wood Dale, IL | 13,783 | 55 | 10.0% |
Royse City, TX | 13,773 | 51 | 2.0% |
Jefferson Valley-Yorktown, NY | 13,786 | 36 | 28.0% |
Bridgetown, OH | 13,786 | 54 | 8.0% |
St. Helens, OR | 13,779 | 18 | 64.0% |