| Month | Temp. (min) | Temp. (max) | Temp. (avg) | Precipitation |
| January | 17°F | 42°F | 28°F | 1.6" |
| February | 20°F | 48°F | 33°F | 0.7" |
| March | 28°F | 60°F | 42°F | 2.4" |
| April | 33°F | 62°F | 46°F | 1.7" |
| May | 41°F | 67°F | 53°F | 3.6" |
| June | 53°F | 83°F | 67°F | 3.1" |
| July | 58°F | 90°F | 73°F | 3.6" |
| August | 55°F | 86°F | 69°F | 5.0" |
| September | 49°F | 81°F | 64°F | 3.1" |
| October | 39°F | 69°F | 52°F | 3.3" |
| November | 24°F | 54°F | 38°F | 1.2" |
| December | 15°F | 41°F | 27°F | 1.0" |
| Index | Iliff | Colorado | National |
| Air quality index | 19 | 38 | 42 |
| Pollution index | 614,319 | 2,068,342 | 2,726,193 |
| Measurement | Total |
| Days measured | 113 |
| Days with good air quality | 110 |
| Days with moderate air quality | 3 |
| Days w/ poor A.Q. for sensitive groups | 0 |
| Days with unhealthy air quality | 0 |
| Pollutant | Total |
| Arsenic | 0.001% |
| Benzene | 0.020% |
| Carbon Tetrachloride | 0.002% |
| Lead | 0.010% |
| Mercury | 0.000% |
| City | Population | Air Quality Index | National Avg. |
| Peetz, CO | 266 | 19 | 62.0% |
| Crook, CO | 170 | 19 | 62.0% |
| Fleming, CO | 684 | 19 | 62.0% |
| Padroni, CO | 64 | 19 | 62.0% |
| Atwood, CO | 159 | 45 | 10.0% |
| Iliff, CO | 354 | 19 | 62.0% |
| City | Population | Air Quality Index | National Avg. |
| Richfield, CA | 354 | 41 | 18.0% |
| Oliver, GA | 354 | 39 | 22.0% |
| Alto Pass, IL | 354 | 44 | 12.0% |
| Glenview Hills, KY | 354 | 49 | 2.0% |
| Virgie, KY | 354 | 45 | 10.0% |
| Iliff, CO | 354 | 19 | 62.0% |