| Month | Temp. (min) | Temp. (max) | Temp. (avg) | Precipitation |
| January | 9°F | 30°F | 20°F | 2.9" |
| February | 12°F | 32°F | 22°F | 2.5" |
| March | 21°F | 41°F | 31°F | 3.6" |
| April | 34°F | 56°F | 45°F | 4.7" |
| May | 44°F | 65°F | 54°F | 3.6" |
| June | 54°F | 74°F | 63°F | 5.5" |
| July | 59°F | 80°F | 69°F | 4.6" |
| August | 56°F | 78°F | 66°F | 3.5" |
| September | 49°F | 71°F | 60°F | 4.0" |
| October | 39°F | 58°F | 48°F | 7.6" |
| November | 30°F | 48°F | 39°F | 5.7" |
| December | 17°F | 35°F | 26°F | 3.8" |
| Index | Dexter | Maine | National |
| Air quality index | 31 | 33 | 42 |
| Pollution index | 3,063,530 | 3,417,521 | 2,726,193 |
| Measurement | Total |
| Days measured | 361 |
| Days with good air quality | 348 |
| Days with moderate air quality | 13 |
| Days w/ poor A.Q. for sensitive groups | 0 |
| Days with unhealthy air quality | 0 |
| Pollutant | Total |
| Arsenic | 0.010% |
| Benzene | 0.020% |
| Carbon Tetrachloride | 0.002% |
| Lead | 0.010% |
| Mercury | 0.004% |
| City | Population | Air Quality Index | National Avg. |
| Dover-Foxcroft, ME | 2,512 | 31 | 38.0% |
| Guilford, ME | 494 | 31 | 38.0% |
| Hartland, ME | 531 | 31 | 38.0% |
| Newport, ME | 1,911 | 31 | 38.0% |
| Dexter, ME | 1,981 | 31 | 38.0% |
| City | Population | Air Quality Index | National Avg. |
| Santa Nella, CA | 1,981 | 48 | 4.0% |
| North Newton, KS | 1,981 | 40 | 20.0% |
| Allegany, NY | 1,981 | 9 | 82.0% |
| Cooper, TX | 1,981 | 325 | 550.0% |
| Nisga'a, BC | 1,981 | n/a | |
| Dexter, ME | 1,981 | 31 | 38.0% |
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