Why stop at city-to-city? With Local Insights, you can compare neighborhoods, zip codes, or even exact addresses. Access 300+ hyperlocal data points—from schools and crime to housing and amenities—to see which area is the better fit.
| Month | Temp. (min) | Temp. (max) | Temp. (avg) | Precipitation |
| January | 15°F | 32°F | 23°F | 1.5" |
| February | 16°F | 34°F | 24°F | 1.4" |
| March | 29°F | 49°F | 38°F | 2.3" |
| April | 39°F | 62°F | 50°F | 3.9" |
| May | 49°F | 73°F | 61°F | 4.3" |
| June | 59°F | 82°F | 70°F | 4.5" |
| July | 62°F | 84°F | 73°F | 4.3" |
| August | 60°F | 82°F | 71°F | 4.3" |
| September | 53°F | 77°F | 64°F | 2.9" |
| October | 42°F | 64°F | 52°F | 3.6" |
| November | 30°F | 50°F | 40°F | 2.1" |
| December | 20°F | 36°F | 28°F | 2.2" |
| Index | Plano | Illinois | National |
| Air quality index | 0 | 41 | 42 |
| Pollution index | 1,874,490 | 3,148,694 | 2,726,193 |
| Measurement | Total |
| Days measured | 335 |
| Days with good air quality | 334 |
| Days with moderate air quality | 1 |
| Days w/ poor A.Q. for sensitive groups | 0 |
| Days with unhealthy air quality | 0 |
| Pollutant | Total |
| Arsenic | 0.002% |
| Benzene | 0.030% |
| Carbon Tetrachloride | 0.010% |
| Lead | 0.010% |
| Mercury | 0.010% |
| City | Population | Air Quality Index | National Avg. |
| Sheridan, IL | 2,829 | 0 | 100.0% |
| Millington, IL | 662 | 0 | 100.0% |
| Montgomery, IL | 19,515 | 0 | 100.0% |
| Plattville, IL | 190 | 0 | 100.0% |
| Big Rock, IL | 1,271 | 0 | 100.0% |
| Plano, IL | 11,058 | 0 | 100.0% |
| City | Population | Air Quality Index | National Avg. |
| Lanham, MD | 11,054 | 47 | 6.0% |
| Holbrook, MA | 11,051 | 43 | 14.0% |
| Ocean City, NJ | 11,065 | 37 | 26.0% |
| Marieville, QC | 11,065 | n/a | |
| La Homa, TX | 11,066 | 42 | 16.0% |
| Plano, IL | 11,058 | 0 | 100.0% |
Here are the best places to live in Illinois
These are the 10 cheapest cities in Illinois
Check out the 10 safest cities in Illinois
Check out the 10 most dangerous cities in Illinois