| Month | Temp. (min) | Temp. (max) | Temp. (avg) | Precipitation |
| January | 8°F | 24°F | 15°F | 1.0" |
| February | 9°F | 27°F | 17°F | 2.9" |
| March | 24°F | 42°F | 32°F | 2.6" |
| April | 37°F | 57°F | 46°F | 5.5" |
| May | 48°F | 70°F | 58°F | 6.3" |
| June | 59°F | 79°F | 68°F | 6.1" |
| July | 63°F | 83°F | 73°F | 6.3" |
| August | 61°F | 80°F | 70°F | 8.3" |
| September | 53°F | 73°F | 62°F | 6.4" |
| October | 40°F | 58°F | 48°F | 5.0" |
| November | 27°F | 43°F | 35°F | 2.4" |
| December | 13°F | 27°F | 19°F | 2.0" |
| Index | Watertown | Minnesota | National |
| Air quality index | 46 | 35 | 42 |
| Pollution index | 1,774,860 | 1,854,519 | 2,726,193 |
| Measurement | Total |
| Days measured | 365 |
| Days with good air quality | 214 |
| Days with moderate air quality | 148 |
| Days w/ poor A.Q. for sensitive groups | 2 |
| Days with unhealthy air quality | 1 |
| Pollutant | Total |
| Arsenic | 0.001% |
| Benzene | 0.030% |
| Carbon Tetrachloride | 0.001% |
| Lead | 0.003% |
| Mercury | 0.001% |
| City | Population | Air Quality Index | National Avg. |
| Howard Lake, MN | 1,897 | 32 | 36.0% |
| Waverly, MN | 1,513 | 32 | 36.0% |
| Victoria, MN | 9,787 | 46 | 8.0% |
| Corcoran, MN | 6,113 | 46 | 8.0% |
| Shorewood, MN | 7,939 | 46 | 8.0% |
| Watertown, MN | 4,473 | 46 | 8.0% |
| City | Population | Air Quality Index | National Avg. |
| South Greeley, WY | 4,473 | 43 | 14.0% |
| Viroqua, WI | 4,472 | 35 | 30.0% |
| Westover, WV | 4,475 | 36 | 28.0% |
| Sherman, IL | 4,470 | 40 | 20.0% |
| Surfside Beach, SC | 4,470 | 14 | 72.0% |
| Watertown, MN | 4,473 | 46 | 8.0% |
Here are the best places to live in Minnesota
See the best places to live in Watertown
Check out the 10 most dangerous cities in Minnesota
Most Dangerous States In The US