| Month | Temp. (min) | Temp. (max) | Temp. (avg) | Precipitation |
| January | 23°F | 40°F | 32°F | 2.6" |
| February | 23°F | 41°F | 32°F | 2.8" |
| March | 30°F | 48°F | 39°F | 3.4" |
| April | 40°F | 60°F | 50°F | 4.5" |
| May | 50°F | 69°F | 59°F | 3.8" |
| June | 60°F | 78°F | 68°F | 4.7" |
| July | 66°F | 84°F | 75°F | 3.1" |
| August | 64°F | 82°F | 74°F | 3.7" |
| September | 58°F | 77°F | 67°F | 3.2" |
| October | 47°F | 66°F | 57°F | 4.5" |
| November | 37°F | 55°F | 46°F | 2.9" |
| December | 30°F | 45°F | 37°F | 4.2" |
| Index | Clinton | Connecticut | National |
| Air quality index | 41 | 43 | 42 |
| Pollution index | 4,117,250 | 8,629,883 | 2,726,193 |
| Measurement | Total |
| Days measured | 365 |
| Days with good air quality | 280 |
| Days with moderate air quality | 71 |
| Days w/ poor A.Q. for sensitive groups | 12 |
| Days with unhealthy air quality | 2 |
| Pollutant | Total |
| Arsenic | 0.010% |
| Benzene | 0.050% |
| Carbon Tetrachloride | 0.010% |
| Lead | 0.010% |
| Mercury | 0.010% |
| City | Population | Air Quality Index | National Avg. |
| Essex Village, CT | 2,757 | 37 | 26.0% |
| Orient, NY | 1,023 | 37 | 26.0% |
| Fenwick, CT | 44 | 37 | 26.0% |
| Old Saybrook Center, CT | 1,984 | 37 | 26.0% |
| East Marion, NY | 1,144 | 37 | 26.0% |
| Clinton, CT | 3,309 | 41 | 18.0% |
| City | Population | Air Quality Index | National Avg. |
| Weaverville, CA | 3,308 | 42 | 16.0% |
| Durand, MI | 3,308 | 38 | 24.0% |
| Long Prairie, MN | 3,308 | 29 | 42.0% |
| Crestview Hills, KY | 3,310 | 54 | 8.0% |
| Carrollton, OH | 3,310 | 46 | 8.0% |
| Clinton, CT | 3,309 | 41 | 18.0% |
Here are the best places to live in Connecticut
See the best places to live in Clinton
Check out the 10 most dangerous cities in Connecticut
Most Dangerous Cities In The US