| Month | Temp. (min) | Temp. (max) | Temp. (avg) | Precipitation |
| January | 19°F | 38°F | 28°F | 2.6" |
| February | 19°F | 40°F | 29°F | 2.6" |
| March | 28°F | 50°F | 38°F | 3.1" |
| April | 38°F | 64°F | 51°F | 3.3" |
| May | 48°F | 74°F | 60°F | 3.1" |
| June | 57°F | 80°F | 68°F | 5.7" |
| July | 62°F | 85°F | 73°F | 5.0" |
| August | 59°F | 82°F | 70°F | 5.4" |
| September | 52°F | 76°F | 63°F | 4.6" |
| October | 42°F | 66°F | 53°F | 4.4" |
| November | 32°F | 53°F | 42°F | 2.5" |
| December | 25°F | 43°F | 33°F | 3.8" |
| Index | Franklin | New Jersey | National |
| Air quality index | 34 | 45 | 42 |
| Pollution index | 3,291,140 | 7,246,891 | 2,726,193 |
| Measurement | Total |
| Days measured | 349 |
| Days with good air quality | 340 |
| Days with moderate air quality | 9 |
| Days w/ poor A.Q. for sensitive groups | 0 |
| Days with unhealthy air quality | 0 |
| Pollutant | Total |
| Arsenic | 0.002% |
| Benzene | 0.050% |
| Carbon Tetrachloride | 0.010% |
| Lead | 0.020% |
| Mercury | 0.001% |
| City | Population | Air Quality Index | National Avg. |
| Andover, NJ | 675 | 34 | 32.0% |
| Mount Arlington, NJ | 5,751 | 34 | 32.0% |
| Wharton, NJ | 6,458 | 34 | 32.0% |
| Branchville, NJ | 1,054 | 34 | 32.0% |
| Newton, NJ | 7,935 | 34 | 32.0% |
| Franklin, NJ | 4,737 | 34 | 32.0% |
| City | Population | Air Quality Index | National Avg. |
| Hillandale, MD | 4,737 | 47 | 6.0% |
| Dundee, FL | 4,738 | 36 | 28.0% |
| Morganville, NJ | 4,738 | 41 | 18.0% |
| Harrington Park, NJ | 4,735 | 51 | 2.0% |
| Blue Point, NY | 4,739 | 43 | 14.0% |
| Franklin, NJ | 4,737 | 34 | 32.0% |
Here are the best places to live in New Jersey
Most Dangerous Cities In The US
These are the 10 cheapest cities in New Jersey
See the best places to live in Franklin