| Month | Temp. (min) | Temp. (max) | Temp. (avg) | Precipitation |
| January | 35°F | 47°F | 40°F | 8.3" |
| February | 36°F | 52°F | 42°F | 5.4" |
| March | 40°F | 56°F | 46°F | 6.0" |
| April | 41°F | 62°F | 50°F | 4.8" |
| May | 47°F | 69°F | 56°F | 5.7" |
| June | 52°F | 73°F | 60°F | 3.6" |
| July | 55°F | 80°F | 65°F | 2.1" |
| August | 55°F | 81°F | 66°F | 2.8" |
| September | 51°F | 75°F | 61°F | 5.1" |
| October | 46°F | 63°F | 53°F | 6.4" |
| November | 40°F | 52°F | 45°F | 8.2" |
| December | 35°F | 45°F | 39°F | 8.9" |
| Index | Ryderwood | Washington | National |
| Air quality index | 18 | 36 | 42 |
| Pollution index | 4,215,410 | 4,541,850 | 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 | 0.005% |
| Benzene | 0.050% |
| Carbon Tetrachloride | 0.004% |
| Lead | 0.030% |
| Mercury | 0.250% |
| City | Population | Air Quality Index | National Avg. |
| Longview Heights, WA | 4,388 | 18 | 64.0% |
| East Cathlamet, WA | 512 | 18 | 64.0% |
| Vader, WA | 696 | 18 | 64.0% |
| Castle Rock, WA | 2,917 | 18 | 64.0% |
| Upper Elochoman, WA | 119 | 18 | 64.0% |
| Ryderwood, WA | 401 | 18 | 64.0% |
| City | Population | Air Quality Index | National Avg. |
| Uriah, AL | 401 | 37 | 26.0% |
| Wilton, AR | 401 | 39 | 22.0% |
| Walker, CA | 401 | 13 | 74.0% |
| Morrison, CO | 401 | 58 | 16.0% |
| Minburn, IA | 401 | 39 | 22.0% |
| Ryderwood, WA | 401 | 18 | 64.0% |
Here are the best places to live in Washington
Most Dangerous Cities In The US
Check out the 10 most dangerous cities in Washington
These are the largest cities in Washington