| Month | Temp. (min) | Temp. (max) | Temp. (avg) | Precipitation |
| January | 18°F | 34°F | 27°F | 4.7" |
| February | 16°F | 36°F | 27°F | 0.9" |
| March | 25°F | 45°F | 36°F | 3.8" |
| April | 38°F | 59°F | 49°F | 9.3" |
| May | 47°F | 68°F | 58°F | 5.4" |
| June | 60°F | 81°F | 71°F | 0.9" |
| July | 64°F | 84°F | 74°F | 3.9" |
| August | 62°F | 85°F | 75°F | 0.0" |
| September | 53°F | 78°F | 67°F | 0.0" |
| October | 46°F | 65°F | 55°F | 5.7" |
| November | 31°F | 50°F | 40°F | 6.4" |
| December | 19°F | 36°F | 27°F | 3.4" |
| Index | Pepperell | Massachusetts | National |
| Air quality index | 37 | 40 | 42 |
| Pollution index | 7,556,320 | 8,399,610 | 2,726,193 |
| Measurement | Total |
| Days measured | 365 |
| Days with good air quality | 353 |
| Days with moderate air quality | 12 |
| 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 | 0.040% |
| Lead | 0.010% |
| Mercury | 0.040% |
| City | Population | Air Quality Index | National Avg. |
| Amherst, NH | 676 | 37 | 26.0% |
| Nashua, NH | 91,471 | 37 | 26.0% |
| Londonderry, NH | 12,432 | 37 | 26.0% |
| East Pepperell, MA | 1,981 | 37 | 26.0% |
| Greenville, NH | 1,041 | 37 | 26.0% |
| Pepperell, MA | 2,750 | 37 | 26.0% |
| City | Population | Air Quality Index | National Avg. |
| Guin, AL | 2,750 | 39 | 22.0% |
| Meredith, NH | 2,750 | 31 | 38.0% |
| Chewelah, WA | 2,750 | 43 | 14.0% |
| Grey, MB | 2,750 | n/a | |
| Edwards AFB, CA | 2,749 | 72 | 44.0% |
| Pepperell, MA | 2,750 | 37 | 26.0% |