| Month | Temp. (min) | Temp. (max) | Temp. (avg) | Precipitation |
| January | 23°F | 44°F | 32°F | 2.1" |
| February | 25°F | 46°F | 35°F | 1.8" |
| March | 36°F | 60°F | 47°F | 3.7" |
| April | 46°F | 71°F | 58°F | 5.3" |
| May | 55°F | 78°F | 66°F | 4.5" |
| June | 65°F | 87°F | 76°F | 4.8" |
| July | 68°F | 90°F | 79°F | 2.9" |
| August | 66°F | 89°F | 77°F | 3.4" |
| September | 58°F | 82°F | 69°F | 3.9" |
| October | 46°F | 70°F | 57°F | 3.0" |
| November | 36°F | 59°F | 46°F | 2.8" |
| December | 27°F | 45°F | 35°F | 3.1" |
| Index | Cottleville | Missouri | National |
| Air quality index | 54 | 97 | 42 |
| Pollution index | 3,042,530 | 1,630,255 | 2,726,193 |
| Measurement | Total |
| Days measured | 365 |
| Days with good air quality | 134 |
| Days with moderate air quality | 221 |
| Days w/ poor A.Q. for sensitive groups | 8 |
| Days with unhealthy air quality | 2 |
| Pollutant | Total |
| Arsenic | 0.010% |
| Benzene | 0.040% |
| Carbon Tetrachloride | 0.010% |
| Lead | 0.010% |
| Mercury | 0.001% |
| City | Population | Air Quality Index | National Avg. |
| Brussels, IL | 113 | 54 | 8.0% |
| Lake St. Louis, MO | 16,357 | 54 | 8.0% |
| Country Life Acres, MO | 52 | 54 | 8.0% |
| Oakland, MO | 1,538 | 54 | 8.0% |
| Valley Park, MO | 6,813 | 54 | 8.0% |
| Cottleville, MO | 5,439 | 54 | 8.0% |
| City | Population | Air Quality Index | National Avg. |
| Eagleville, PA | 5,439 | 51 | 2.0% |
| San Leon, TX | 5,439 | 52 | 4.0% |
| Carver, MN | 5,438 | 46 | 8.0% |
| L'Épiphanie, QC | 5,436 | n/a | |
| Cottonwood, CA | 5,435 | 42 | 16.0% |
| Cottleville, MO | 5,439 | 54 | 8.0% |
Here are the best places to live in Missouri
10 Best cities in Missouri for employment
These are the 10 most affordable cities in Missouri
Top 10 cities in Missouri with the best education system