| Month | Temp. (min) | Temp. (max) | Temp. (avg) | Precipitation |
| January | 37°F | 55°F | 45°F | 5.4" |
| February | 37°F | 57°F | 46°F | 3.6" |
| March | 46°F | 69°F | 56°F | 3.3" |
| April | 54°F | 76°F | 65°F | 4.4" |
| May | 63°F | 83°F | 72°F | 4.7" |
| June | 70°F | 92°F | 80°F | 2.0" |
| July | 72°F | 92°F | 81°F | 4.3" |
| August | 72°F | 94°F | 82°F | 3.2" |
| September | 66°F | 87°F | 75°F | 8.2" |
| October | 53°F | 77°F | 64°F | 6.2" |
| November | 44°F | 67°F | 54°F | 2.5" |
| December | 38°F | 57°F | 46°F | 6.3" |
| Index | Indianola | Mississippi | National |
| Air quality index | 43 | 40 | 42 |
| Pollution index | 1,165,390 | 1,514,109 | 2,726,193 |
| Measurement | Total |
| Days measured | 364 |
| Days with good air quality | 270 |
| Days with moderate air quality | 94 |
| Days w/ poor A.Q. for sensitive groups | 0 |
| Days with unhealthy air quality | 0 |
| Pollutant | Total |
| Arsenic | 0.001% |
| Benzene | 0.040% |
| Carbon Tetrachloride | 0.002% |
| Lead | 0.010% |
| Mercury | 0.000% |
| City | Population | Air Quality Index | National Avg. |
| Inverness, MS | 863 | 43 | 14.0% |
| Doddsville, MS | 232 | 43 | 14.0% |
| Arcola, MS | 305 | 43 | 14.0% |
| Isola, MS | 787 | 43 | 14.0% |
| Leland, MS | 4,020 | 43 | 14.0% |
| Indianola, MS | 9,550 | 43 | 14.0% |
| City | Population | Air Quality Index | National Avg. |
| Harvard, IL | 9,547 | 42 | 16.0% |
| Sellersburg, IN | 9,547 | 49 | 2.0% |
| Tomah, WI | 9,547 | 35 | 30.0% |
| Eagle Point, OR | 9,546 | 36 | 28.0% |
| Walnut Grove, WA | 9,546 | 38 | 24.0% |
| Indianola, MS | 9,550 | 43 | 14.0% |