| Month | Temp. (min) | Temp. (max) | Temp. (avg) | Precipitation |
| January | 24°F | 45°F | 33°F | 2.4" |
| February | 25°F | 48°F | 35°F | 2.2" |
| March | 37°F | 61°F | 48°F | 3.6" |
| April | 47°F | 72°F | 59°F | 5.4" |
| May | 57°F | 80°F | 68°F | 4.6" |
| June | 67°F | 89°F | 78°F | 5.2" |
| July | 70°F | 92°F | 81°F | 4.2" |
| August | 69°F | 91°F | 79°F | 3.6" |
| September | 61°F | 84°F | 72°F | 4.3" |
| October | 48°F | 72°F | 60°F | 3.4" |
| November | 37°F | 60°F | 48°F | 3.4" |
| December | 27°F | 47°F | 37°F | 3.5" |
| Index | Hazelwood | Missouri | National |
| Air quality index | 54 | 97 | 42 |
| Pollution index | 8,870,230 | 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 | 0.180% |
| Benzene | 0.060% |
| Carbon Tetrachloride | 0.020% |
| Lead | 0.030% |
| Mercury | 0.120% |
| City | Population | Air Quality Index | National Avg. |
| Oakland, MO | 1,538 | 54 | 8.0% |
| Cahokia, IL | 14,035 | 54 | 8.0% |
| Twin Oaks, MO | 520 | 54 | 8.0% |
| Hanley Hills, MO | 1,853 | 54 | 8.0% |
| Pagedale, MO | 3,301 | 54 | 8.0% |
| Hazelwood, MO | 25,222 | 54 | 8.0% |
| City | Population | Air Quality Index | National Avg. |
| Watertown, NY | 25,224 | 35 | 30.0% |
| Reading, MA | 25,236 | 43 | 14.0% |
| Lunenburg, NS | 25,205 | n/a | |
| Collingwood, ON | 25,244 | n/a | |
| Zanesville, OH | 25,246 | 41 | 18.0% |
| Hazelwood, MO | 25,222 | 54 | 8.0% |
Here are the best places to live in Missouri
Safest Cities In The US
See the best places to live in Hazelwood
Check out the 10 most dangerous cities in Missouri