| Month | Temp. (min) | Temp. (max) | Temp. (avg) | Precipitation |
| January | 19°F | 39°F | 29°F | 2.7" |
| February | 19°F | 40°F | 29°F | 3.0" |
| March | 28°F | 49°F | 38°F | 3.5" |
| April | 38°F | 62°F | 50°F | 4.0" |
| May | 48°F | 73°F | 60°F | 3.3" |
| June | 57°F | 79°F | 68°F | 5.0" |
| July | 63°F | 85°F | 74°F | 3.9" |
| August | 60°F | 82°F | 71°F | 4.1" |
| September | 54°F | 77°F | 65°F | 3.7" |
| October | 43°F | 66°F | 54°F | 4.4" |
| November | 33°F | 54°F | 43°F | 3.4" |
| December | 26°F | 44°F | 34°F | 4.0" |
| Index | Moosup | Connecticut | National |
| Air quality index | 37 | 43 | 42 |
| Pollution index | 2,960,790 | 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 | 0.003% |
| Benzene | 0.030% |
| Carbon Tetrachloride | 0.010% |
| Lead | 0.020% |
| Mercury | 0.005% |
| City | Population | Air Quality Index | National Avg. |
| East Brooklyn, CT | 2,153 | 33 | 34.0% |
| Wauregan, CT | 1,540 | 33 | 34.0% |
| Brooklyn, CT | 1,158 | 33 | 34.0% |
| Putnam, CT | 7,358 | 33 | 34.0% |
| Danielson, CT | 4,138 | 33 | 34.0% |
| Moosup, CT | 4,011 | 37 | 26.0% |
| City | Population | Air Quality Index | National Avg. |
| Romeo, MI | 4,011 | 56 | 12.0% |
| Hunter, OH | 4,010 | 47 | 6.0% |
| West Columbia, TX | 4,010 | 52 | 4.0% |
| Oracle, AZ | 4,012 | 47 | 6.0% |
| Ridgeland, SC | 4,013 | 29 | 42.0% |
| Moosup, CT | 4,011 | 37 | 26.0% |