| Month | Temp. (min) | Temp. (max) | Temp. (avg) | Precipitation |
| January | 23°F | 40°F | 32°F | 2.5" |
| February | 23°F | 40°F | 32°F | 2.1" |
| March | 30°F | 47°F | 38°F | 3.3" |
| April | 39°F | 58°F | 48°F | 3.1" |
| May | 48°F | 66°F | 57°F | 3.6" |
| June | 58°F | 75°F | 66°F | 3.6" |
| July | 65°F | 81°F | 72°F | 2.8" |
| August | 63°F | 80°F | 71°F | 3.0" |
| September | 57°F | 75°F | 66°F | 3.3" |
| October | 47°F | 65°F | 56°F | 4.4" |
| November | 37°F | 55°F | 46°F | 2.9" |
| December | 29°F | 46°F | 37°F | 3.4" |
| Index | Conning Towers Nautilus Park | Connecticut | National |
| Air quality index | 37 | 43 | 42 |
| Pollution index | 4,117,250 | 8,629,883 | 2,726,193 |
| Measurement | Total |
| Days measured | 364 |
| Days with good air quality | 323 |
| Days with moderate air quality | 34 |
| Days w/ poor A.Q. for sensitive groups | 7 |
| Days with unhealthy air quality | 0 |
| 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. |
| Colchester, CT | 5,147 | 33 | 34.0% |
| Fishers Island, NY | 61 | 37 | 26.0% |
| Oxoboxo River, CT | 2,772 | 37 | 26.0% |
| Pawcatuck, CT | 5,024 | 37 | 26.0% |
| Groton, CT | 8,999 | 37 | 26.0% |
| Conning Towers Nautilus Park, CT | 9,606 | 37 | 26.0% |
| City | Population | Air Quality Index | National Avg. |
| Picnic Point, WA | 9,607 | 45 | 10.0% |
| Brookdale, NJ | 9,604 | 51 | 2.0% |
| Arnprior, ON | 9,608 | n/a | |
| St. Pete Beach, FL | 9,603 | 38 | 24.0% |
| Howell, MI | 9,610 | 40 | 20.0% |
| Conning Towers Nautilus Park, CT | 9,606 | 37 | 26.0% |
Here are the best places to live in Connecticut
Check out the 10 most dangerous cities in Connecticut
Most Dangerous Cities In The US
Check out the 10 safest cities in Connecticut