
| Month | Low | High |
|---|---|---|
| Jan | 36.0°F | 46.9°F |
| Feb | 37.1°F | 50.5°F |
| Mar | 39.2°F | 54.5°F |
| Apr | 42.5°F | 59.3°F |
| May | 48.2°F | 64.9°F |
| Jun | 52.7°F | 69.5°F |
| Jul | 56.4°F | 74.5°F |
| Aug | 57.1°F | 74.9°F |
| Sept | 52.6°F | 69.9°F |
| Oct | 46.4°F | 60.3°F |
| Nov | 40.4°F | 51.5°F |
| Dec | 36.1°F | 46.5°F |
Seattle C.O.'s coldest month is January when the average temperature overnight is 36.0°F. In August, the warmest month, the average day time temperature rises to 74.9°F.

| Month | Precipitation |
|---|---|
| Jan | 5.24in. |
| Feb | 4.09in. |
| Mar | 3.92in. |
| Apr | 2.75in. |
| May | 2.03in. |
| Jun | 1.55in. |
| Jul | 0.93in. |
| Aug | 1.16in. |
| Sept | 1.61in. |
| Oct | 3.24in. |
| Nov | 5.67in. |
| Dec | 6.06in. |
The driest month in Seattle C.O. is July with 0.93 inches of precipitation, and with 6.06 inches December is the wettest month.