| Month | Temp. (min) | Temp. (max) | Temp. (avg) | Precipitation |
| January | 12°F | 29°F | 20°F | 0.8" |
| February | 14°F | 32°F | 23°F | 1.0" |
| March | 28°F | 48°F | 37°F | 2.1" |
| April | 39°F | 63°F | 50°F | 4.6" |
| May | 50°F | 73°F | 61°F | 3.9" |
| June | 60°F | 81°F | 70°F | 7.0" |
| July | 63°F | 84°F | 73°F | 4.8" |
| August | 61°F | 82°F | 71°F | 4.7" |
| September | 53°F | 76°F | 64°F | 4.0" |
| October | 42°F | 63°F | 52°F | 3.1" |
| November | 29°F | 49°F | 38°F | 2.1" |
| December | 17°F | 33°F | 25°F | 1.9" |
| Index | Fairfax | Iowa | National |
| Air quality index | 39 | 39 | 42 |
| Pollution index | 5,075,380 | 1,154,535 | 2,726,193 |
| Measurement | Total |
| Days measured | 365 |
| Days with good air quality | 287 |
| Days with moderate air quality | 78 |
| Days w/ poor A.Q. for sensitive groups | 0 |
| Days with unhealthy air quality | 0 |
| Pollutant | Total |
| Arsenic | 0.070% |
| Benzene | 0.050% |
| Carbon Tetrachloride | 2.000% |
| Lead | 0.040% |
| Mercury | 0.100% |
| City | Population | Air Quality Index | National Avg. |
| Tiffin, IA | 3,779 | 35 | 30.0% |
| North Liberty, IA | 19,159 | 35 | 30.0% |
| Solon, IA | 2,690 | 35 | 30.0% |
| Oxford, IA | 707 | 35 | 30.0% |
| Cedar Rapids, IA | 133,125 | 39 | 22.0% |
| Fairfax, IA | 2,770 | 39 | 22.0% |
| City | Population | Air Quality Index | National Avg. |
| Green Harbor-Cedar Crest, MA | 2,770 | 43 | 14.0% |
| Souris-Glenwood, MB | 2,770 | n/a | |
| Big Lake, AK | 2,769 | 31 | 38.0% |
| Knob Noster, MO | 2,769 | 47 | 6.0% |
| Dallas, PA | 2,769 | 38 | 24.0% |
| Fairfax, IA | 2,770 | 39 | 22.0% |
Here are the best places to live in Iowa
Check out the 10 safest cities in Iowa
These are the largest cities in Iowa
See the best places to live in Fairfax