| Month | Temp. (min) | Temp. (max) | Temp. (avg) | Precipitation |
| January | 14°F | 32°F | 23°F | 2.9" |
| February | 14°F | 34°F | 24°F | 3.3" |
| March | 22°F | 43°F | 32°F | 3.7" |
| April | 34°F | 57°F | 45°F | 3.3" |
| May | 45°F | 69°F | 56°F | 3.8" |
| June | 54°F | 76°F | 64°F | 4.9" |
| July | 59°F | 81°F | 70°F | 4.3" |
| August | 56°F | 79°F | 67°F | 4.4" |
| September | 50°F | 73°F | 61°F | 3.9" |
| October | 40°F | 61°F | 49°F | 5.5" |
| November | 30°F | 49°F | 38°F | 2.9" |
| December | 21°F | 38°F | 29°F | 4.0" |
| Index | Jaffrey | New Hampshire | National |
| Air quality index | 34 | 34 | 42 |
| Pollution index | 6,602,810 | 3,959,618 | 2,726,193 |
| Measurement | Total |
| Days measured | 365 |
| Days with good air quality | 348 |
| Days with moderate air quality | 17 |
| Days w/ poor A.Q. for sensitive groups | 0 |
| Days with unhealthy air quality | 0 |
| Pollutant | Total |
| Arsenic | 0.010% |
| Benzene | 0.070% |
| Carbon Tetrachloride | 0.020% |
| Lead | 0.060% |
| Mercury | 0.010% |
| City | Population | Air Quality Index | National Avg. |
| Peterborough, NH | 2,704 | 34 | 32.0% |
| Baldwinville, MA | 2,137 | 34 | 32.0% |
| Orange, MA | 3,882 | 34 | 32.0% |
| Keene, NH | 22,823 | 34 | 32.0% |
| Winchendon, MA | 4,673 | 34 | 32.0% |
| Jaffrey, NH | 2,750 | 34 | 32.0% |
| City | Population | Air Quality Index | National Avg. |
| Dodge Center, MN | 2,750 | 36 | 28.0% |
| Grey, MB | 2,750 | n/a | |
| Saint-Prime, QC | 2,749 | n/a | |
| Reed Creek, GA | 2,751 | 31 | 38.0% |
| Lagrange, IN | 2,751 | 37 | 26.0% |
| Jaffrey, NH | 2,750 | 34 | 32.0% |
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