| Month | Temp. (min) | Temp. (max) | Temp. (avg) | Precipitation |
| January | 13°F | 29°F | 20°F | 0.2" |
| February | 14°F | 31°F | 22°F | 2.0" |
| March | 29°F | 47°F | 36°F | 0.7" |
| April | 39°F | 61°F | 49°F | 3.9" |
| May | 50°F | 73°F | 61°F | 5.8" |
| June | 61°F | 82°F | 71°F | 2.9" |
| July | 64°F | 85°F | 74°F | 2.8" |
| August | 62°F | 81°F | 70°F | 2.6" |
| September | 54°F | 76°F | 64°F | 2.7" |
| October | 42°F | 62°F | 51°F | 1.9" |
| November | 29°F | 49°F | 37°F | 0.9" |
| December | 17°F | 32°F | 24°F | 3.5" |
| Index | Aspinwall | Iowa | National |
| Air quality index | 40 | 39 | 42 |
| Pollution index | 517,691 | 1,154,535 | 2,726,193 |
| Measurement | Total |
| Days measured | 365 |
| Days with good air quality | 283 |
| Days with moderate air quality | 82 |
| 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 | 0.002% |
| Mercury | 0.000% |
| City | Population | Air Quality Index | National Avg. |
| Denison, IA | 8,630 | 35 | 30.0% |
| Vail, IA | 612 | 35 | 30.0% |
| Deloit, IA | 312 | 35 | 30.0% |
| Westside, IA | 258 | 35 | 30.0% |
| Arcadia, IA | 1,013 | 37 | 26.0% |
| Aspinwall, IA | 22 | 40 | 20.0% |
| City | Population | Air Quality Index | National Avg. |
| Dot Lake Village, AK | 22 | 38 | 24.0% |
| Pedro Bay, AK | 22 | 31 | 38.0% |
| Bucks Lake, CA | 22 | 46 | 8.0% |
| Old Station, CA | 22 | 42 | 16.0% |
| Tennant, CA | 22 | 29 | 42.0% |
| Aspinwall, IA | 22 | 40 | 20.0% |