| Month | Temp. (min) | Temp. (max) | Temp. (avg) | Precipitation |
| January | 19°F | 34°F | 26°F | 4.0" |
| February | 20°F | 34°F | 27°F | 4.2" |
| March | 27°F | 44°F | 35°F | 5.1" |
| April | 39°F | 59°F | 48°F | 4.9" |
| May | 48°F | 67°F | 56°F | 4.2" |
| June | 58°F | 75°F | 66°F | 5.3" |
| July | 63°F | 80°F | 71°F | 6.2" |
| August | 62°F | 79°F | 70°F | 3.6" |
| September | 55°F | 72°F | 63°F | 4.3" |
| October | 44°F | 60°F | 51°F | 7.5" |
| November | 35°F | 50°F | 42°F | 5.1" |
| December | 24°F | 37°F | 30°F | 4.7" |
| Index | North Brookfield | Massachusetts | National |
| Air quality index | 40 | 40 | 42 |
| Pollution index | 7,859,360 | 8,399,610 | 2,726,193 |
| Measurement | Total |
| Days measured | 365 |
| Days with good air quality | 312 |
| Days with moderate air quality | 52 |
| Days w/ poor A.Q. for sensitive groups | 1 |
| Days with unhealthy air quality | 0 |
| Pollutant | Total |
| Arsenic | 0.030% |
| Benzene | 0.070% |
| Carbon Tetrachloride | 0.030% |
| Lead | 0.320% |
| Mercury | 0.070% |
| City | Population | Air Quality Index | National Avg. |
| Palmer Town, MA | 12,662 | 40 | 20.0% |
| Spencer, MA | 6,007 | 40 | 20.0% |
| Worcester, MA | 189,035 | 40 | 20.0% |
| Southbridge Town, MA | 17,257 | 40 | 20.0% |
| Sturbridge, MA | 2,156 | 40 | 20.0% |
| North Brookfield, MA | 2,518 | 40 | 20.0% |
| City | Population | Air Quality Index | National Avg. |
| Hallowell, ME | 2,518 | 28 | 44.0% |
| Kure Beach, NC | 2,518 | 34 | 32.0% |
| Crooksville, OH | 2,518 | 25 | 50.0% |
| Freeport, FL | 2,517 | 31 | 38.0% |
| Guyton, GA | 2,517 | 39 | 22.0% |
| North Brookfield, MA | 2,518 | 40 | 20.0% |