| Month | Temp. (min) | Temp. (max) | Temp. (avg) | Precipitation |
| January | 11°F | 30°F | 20°F | 1.5" |
| February | 13°F | 33°F | 23°F | 1.5" |
| March | 24°F | 47°F | 35°F | 2.6" |
| April | 35°F | 61°F | 48°F | 4.4" |
| May | 46°F | 73°F | 59°F | 4.0" |
| June | 57°F | 81°F | 69°F | 5.9" |
| July | 60°F | 85°F | 73°F | 4.9" |
| August | 59°F | 83°F | 71°F | 4.8" |
| September | 51°F | 77°F | 63°F | 3.5" |
| October | 40°F | 63°F | 51°F | 3.2" |
| November | 28°F | 49°F | 38°F | 2.1" |
| December | 17°F | 34°F | 25°F | 2.3" |
| Index | Windsor | Wisconsin | National |
| Air quality index | 39 | 69 | 42 |
| Pollution index | 350,021 | 2,842,418 | 2,726,193 |
| Measurement | Total |
| Days measured | 365 |
| Days with good air quality | 285 |
| Days with moderate air quality | 80 |
| Days w/ poor A.Q. for sensitive groups | 0 |
| Days with unhealthy air quality | 0 |
| Pollutant | Total |
| Arsenic | 0.003% |
| Benzene | 0.010% |
| Carbon Tetrachloride | 0.001% |
| Lead | 0.001% |
| Mercury | 0.000% |
| City | Population | Air Quality Index | National Avg. |
| Merrimac, WI | 688 | 35 | 30.0% |
| Poynette, WI | 2,559 | 35 | 30.0% |
| Lake Wisconsin, WI | 4,736 | 35 | 30.0% |
| Lodi, WI | 3,180 | 35 | 30.0% |
| Marshall, WI | 4,124 | 37 | 26.0% |
| Windsor, WI | 7,603 | 39 | 22.0% |
| City | Population | Air Quality Index | National Avg. |
| Palmer, AK | 7,603 | 31 | 38.0% |
| Winooski, VT | 7,608 | 37 | 26.0% |
| Connellsville, PA | 7,597 | 36 | 28.0% |
| Swainsboro, GA | 7,596 | 47 | 6.0% |
| Wildwood, FL | 7,610 | 38 | 24.0% |
| Windsor, WI | 7,603 | 39 | 22.0% |