| Month | Temp. (min) | Temp. (max) | Temp. (avg) | Precipitation |
| January | 20°F | 38°F | 28°F | 5.1" |
| February | 20°F | 40°F | 29°F | 3.4" |
| March | 29°F | 50°F | 38°F | 3.8" |
| April | 39°F | 64°F | 51°F | 4.0" |
| May | 49°F | 73°F | 61°F | 4.1" |
| June | 58°F | 80°F | 68°F | 5.3" |
| July | 63°F | 85°F | 73°F | 6.2" |
| August | 60°F | 82°F | 70°F | 5.8" |
| September | 54°F | 76°F | 64°F | 4.5" |
| October | 43°F | 65°F | 53°F | 4.8" |
| November | 33°F | 53°F | 43°F | 2.9" |
| December | 27°F | 43°F | 34°F | 4.8" |
| Index | Dover | New Jersey | National |
| Air quality index | 34 | 45 | 42 |
| Pollution index | 8,169,930 | 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 | 0.010% |
| Benzene | 0.070% |
| Carbon Tetrachloride | 0.030% |
| Lead | 0.020% |
| Mercury | 0.010% |
| City | Population | Air Quality Index | National Avg. |
| Mendham, NJ | 4,880 | 34 | 32.0% |
| Budd Lake, NJ | 10,444 | 34 | 32.0% |
| Hopatcong, NJ | 14,228 | 34 | 32.0% |
| Mount Arlington, NJ | 5,751 | 34 | 32.0% |
| Succasunna, NJ | 9,367 | 34 | 32.0% |
| Dover, NJ | 17,866 | 34 | 32.0% |
| City | Population | Air Quality Index | National Avg. |
| St. Michael, MN | 17,871 | 46 | 8.0% |
| Canby, OR | 17,860 | 38 | 24.0% |
| North Babylon, NY | 17,872 | 51 | 2.0% |
| Jenison, MI | 17,851 | 38 | 24.0% |
| Steubenville, OH | 17,882 | 46 | 8.0% |
| Dover, NJ | 17,866 | 34 | 32.0% |
Here are the best places to live in New Jersey
Check out the 10 safest cities in New Jersey
See the best places to live in Dover
These are the 10 cheapest cities in New Jersey