| Month | Temp. (min) | Temp. (max) | Temp. (avg) | Precipitation |
| January | -1°F | 15°F | 7°F | 5.1" |
| February | -3°F | 14°F | 6°F | 5.8" |
| March | 6°F | 21°F | 13°F | 6.2" |
| April | 19°F | 32°F | 25°F | 7.8" |
| May | 32°F | 44°F | 37°F | 8.4" |
| June | 40°F | 51°F | 45°F | 9.7" |
| July | 45°F | 55°F | 50°F | 9.0" |
| August | 42°F | 54°F | 48°F | 8.6" |
| September | 38°F | 49°F | 44°F | 6.7" |
| October | 27°F | 38°F | 32°F | 10.4" |
| November | 16°F | 30°F | 23°F | 7.0" |
| December | 5°F | 21°F | 13°F | 8.7" |
| Index | Bartlett | New Hampshire | National |
| Air quality index | 40 | 34 | 42 |
| Pollution index | 2,712,920 | 3,959,618 | 2,726,193 |
| Measurement | Total |
| Days measured | 324 |
| Days with good air quality | 314 |
| Days with moderate air quality | 10 |
| Days w/ poor A.Q. for sensitive groups | 0 |
| Days with unhealthy air quality | 0 |
| Pollutant | Total |
| Arsenic | 0.030% |
| Benzene | 0.020% |
| Carbon Tetrachloride | 0.010% |
| Lead | 0.050% |
| Mercury | 0.070% |
| City | Population | Air Quality Index | National Avg. |
| Conway, NH | 3,965 | 31 | 38.0% |
| North Conway, NH | 2,410 | 40 | 20.0% |
| Fryeburg, ME | 1,533 | 40 | 20.0% |
| Bartlett, NH | 184 | 40 | 20.0% |
| City | Population | Air Quality Index | National Avg. |
| Deer Creek, AZ | 184 | 74 | 48.0% |
| Clio, CA | 184 | 44 | 12.0% |
| Lodoga, CA | 184 | 31 | 38.0% |
| Tooleville, CA | 184 | 60 | 20.0% |
| Farmington, DE | 184 | 36 | 28.0% |
| Bartlett, NH | 184 | 40 | 20.0% |
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