| Month | Temp. (min) | Temp. (max) | Temp. (avg) | Precipitation |
| January | 16°F | 34°F | 25°F | 2.3" |
| February | 18°F | 36°F | 27°F | 2.3" |
| March | 29°F | 49°F | 39°F | 2.8" |
| April | 38°F | 63°F | 50°F | 3.9" |
| May | 48°F | 73°F | 60°F | 5.4" |
| June | 59°F | 83°F | 71°F | 4.5" |
| July | 64°F | 86°F | 75°F | 5.2" |
| August | 63°F | 84°F | 74°F | 4.4" |
| September | 56°F | 78°F | 66°F | 3.6" |
| October | 44°F | 65°F | 54°F | 3.4" |
| November | 32°F | 52°F | 42°F | 2.3" |
| December | 21°F | 38°F | 29°F | 2.9" |
| Index | Norridge | Illinois | National |
| Air quality index | 60 | 41 | 50 |
| Pollution index | 3,795,410 | 3,347,295 | 5,066,862 |
| Measurement | Total |
| Days measured | 365 |
| Days with good air quality | 72 |
| Days with moderate air quality | 281 |
| Days w/ poor A.Q. for sensitive groups | 11 |
| Days with unhealthy air quality | 1 |
| Pollutant | Total |
| Arsenic | 0.030% |
| Benzene | 0.050% |
| Carbon Tetrachloride | 0.010% |
| Lead | 0.003% |
| Mercury | 0.310% |
| City, State | Population | Air Quality Index | National Avg. |
| Forest Park, IL | 14,137 | 60 | 20% |
| Glendale Heights, IL | 34,395 | 60 | 20% |
| Harwood Heights, IL | 8,628 | 60 | 20% |
| Indian Head Park, IL | 3,823 | 60 | 20% |
| Kenilworth, IL | 2,613 | 60 | 20% |
| Norridge, IL | 15,023 | 60 | 20% |
| City, State | Population | Air Quality Index | National Avg. |
| Live Oak, TX | 15,021 | 45 | 10% |
| Batavia, NY | 15,012 | 36 | 28% |
| Greeneville, TN | 15,035 | 39 | 22% |
| Clemson, SC | 15,008 | 27 | 46% |
| Harrison, NJ | 15,007 | 53 | 6% |
| Norridge, IL | 15,023 | 60 | 20% |