| Month | Temp. (min) | Temp. (max) | Temp. (avg) | Precipitation |
| January | 12°F | 30°F | 21°F | 0.8" |
| February | 14°F | 34°F | 23°F | 1.0" |
| March | 28°F | 49°F | 37°F | 2.2" |
| April | 39°F | 63°F | 49°F | 4.1" |
| May | 49°F | 73°F | 60°F | 5.2" |
| June | 60°F | 83°F | 71°F | 7.1" |
| July | 64°F | 86°F | 75°F | 4.2" |
| August | 62°F | 83°F | 71°F | 5.5" |
| September | 53°F | 77°F | 63°F | 2.8" |
| October | 41°F | 64°F | 51°F | 4.0" |
| November | 28°F | 49°F | 38°F | 3.7" |
| December | 16°F | 33°F | 24°F | 2.5" |
| Index | Pierson | Iowa | National |
| Air quality index | 35 | 39 | 42 |
| Pollution index | 397,267 | 1,154,535 | 2,726,193 |
| Measurement | Total |
| Days measured | 364 |
| Days with good air quality | 322 |
| Days with moderate air quality | 42 |
| Days w/ poor A.Q. for sensitive groups | 0 |
| Days with unhealthy air quality | 0 |
| Pollutant | Total |
| Arsenic | 0.000% |
| Benzene | 0.010% |
| Carbon Tetrachloride | 0.001% |
| Lead | 0.000% |
| Mercury | 0.000% |
| City | Population | Air Quality Index | National Avg. |
| Anthon, IA | 587 | 35 | 30.0% |
| Washta, IA | 191 | 35 | 30.0% |
| Climbing Hill, IA | 89 | 35 | 30.0% |
| Correctionville, IA | 1,011 | 35 | 30.0% |
| Kingsley, IA | 1,495 | 35 | 30.0% |
| Pierson, IA | 358 | 35 | 30.0% |
| City | Population | Air Quality Index | National Avg. |
| Vinegar Bend, AL | 358 | 42 | 16.0% |
| Donaldson, AR | 358 | 32 | 36.0% |
| Evening Shade, AR | 358 | 36 | 28.0% |
| Loda, IL | 358 | 42 | 16.0% |
| Martinton, IL | 358 | 42 | 16.0% |
| Pierson, IA | 358 | 35 | 30.0% |