| Month | Temp. (min) | Temp. (max) | Temp. (avg) | Precipitation |
| January | 23°F | 41°F | 32°F | 3.3" |
| February | 23°F | 42°F | 32°F | 3.6" |
| March | 30°F | 50°F | 39°F | 4.0" |
| April | 41°F | 62°F | 50°F | 4.3" |
| May | 50°F | 71°F | 59°F | 3.9" |
| June | 60°F | 80°F | 69°F | 4.9" |
| July | 67°F | 85°F | 76°F | 3.5" |
| August | 66°F | 84°F | 74°F | 4.2" |
| September | 59°F | 78°F | 68°F | 3.8" |
| October | 48°F | 67°F | 57°F | 4.7" |
| November | 38°F | 56°F | 47°F | 3.0" |
| December | 29°F | 46°F | 38°F | 5.4" |
| Index | Trumbull | Connecticut | National |
| Air quality index | 43 | 43 | 42 |
| Pollution index | 14,500,300 | 8,629,883 | 2,726,193 |
| Measurement | Total |
| Days measured | 365 |
| Days with good air quality | 262 |
| Days with moderate air quality | 82 |
| Days w/ poor A.Q. for sensitive groups | 18 |
| Days with unhealthy air quality | 3 |
| Pollutant | Total |
| Arsenic | 0.030% |
| Benzene | 0.140% |
| Carbon Tetrachloride | 0.050% |
| Lead | 0.080% |
| Mercury | 0.060% |
| City | Population | Air Quality Index | National Avg. |
| Woodmont, CT | 1,601 | 41 | 18.0% |
| Derby, CT | 12,420 | 41 | 18.0% |
| Orange, CT | 13,928 | 41 | 18.0% |
| New Haven, CT | 130,381 | 41 | 18.0% |
| Ansonia, CT | 18,709 | 41 | 18.0% |
| Trumbull, CT | 36,477 | 43 | 14.0% |
| City | Population | Air Quality Index | National Avg. |
| Dunedin, FL | 36,480 | 43 | 14.0% |
| Oakton, VA | 36,468 | 47 | 6.0% |
| Phenix City, AL | 36,461 | 42 | 16.0% |
| Bartlesville, OK | 36,495 | 45 | 10.0% |
| Kearns, UT | 36,457 | 51 | 2.0% |
| Trumbull, CT | 36,477 | 43 | 14.0% |
Here are the best places to live in Connecticut
Check out the 10 most dangerous cities in Connecticut
Safest Cities In The US
These are the 10 cheapest cities in Connecticut