| Month | Temp. (min) | Temp. (max) | Temp. (avg) | Precipitation |
| January | 2°F | 29°F | 14°F | 2.9" |
| February | 6°F | 35°F | 19°F | 2.1" |
| March | 14°F | 42°F | 27°F | 2.7" |
| April | 20°F | 49°F | 33°F | 1.8" |
| May | 27°F | 60°F | 43°F | 1.8" |
| June | 33°F | 70°F | 52°F | 1.5" |
| July | 38°F | 82°F | 60°F | 0.6" |
| August | 35°F | 80°F | 57°F | 0.6" |
| September | 29°F | 71°F | 48°F | 1.3" |
| October | 24°F | 56°F | 37°F | 2.2" |
| November | 15°F | 40°F | 25°F | 2.7" |
| December | 4°F | 27°F | 15°F | 3.5" |
| Index | Ketchum | Idaho | National |
| Air quality index | 20 | 32 | 42 |
| Pollution index | 1,651,620 | 2,063,710 | 2,726,193 |
| Measurement | Total |
| Days measured | 365 |
| Days with good air quality | 361 |
| Days with moderate air quality | 4 |
| 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 | 0.020% |
| Mercury | 0.001% |
| City | Population | Air Quality Index | National Avg. |
| Hailey, ID | 8,575 | 20 | 60.0% |
| Sun Valley, ID | 1,581 | 20 | 60.0% |
| Ketchum, ID | 2,843 | 20 | 60.0% |
| City | Population | Air Quality Index | National Avg. |
| Cache, OK | 2,843 | 43 | 14.0% |
| St. Clair, PA | 2,842 | 42 | 16.0% |
| Ferris, TX | 2,842 | 51 | 2.0% |
| Somerset, WI | 2,842 | 46 | 8.0% |
| Cetronia, PA | 2,844 | 42 | 16.0% |
| Ketchum, ID | 2,843 | 20 | 60.0% |
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