| Month | Temp. (min) | Temp. (max) | Temp. (avg) | Precipitation |
| January | 25°F | 34°F | 29°F | n/a |
| February | 25°F | 37°F | 30°F | n/a |
| March | 32°F | 47°F | 38°F | n/a |
| April | 35°F | 56°F | 44°F | n/a |
| May | 43°F | 68°F | 55°F | n/a |
| June | 48°F | 71°F | 58°F | n/a |
| July | 54°F | 84°F | 69°F | n/a |
| August | 54°F | 84°F | 68°F | n/a |
| September | 47°F | 73°F | 59°F | n/a |
| October | 37°F | 55°F | 45°F | n/a |
| November | 29°F | 40°F | 34°F | n/a |
| December | 26°F | 34°F | 30°F | n/a |
| Index | Pioneer Junction | Montana | National |
| Air quality index | 37 | 34 | 42 |
| Pollution index | 4,670,990 | 834,473 | 2,726,193 |
| Measurement | Total |
| Days measured | 365 |
| Days with good air quality | 302 |
| Days with moderate air quality | 62 |
| Days w/ poor A.Q. for sensitive groups | 1 |
| Days with unhealthy air quality | 0 |
| Pollutant | Total |
| Arsenic | 0.050% |
| Benzene | 0.060% |
| Carbon Tetrachloride | 0.010% |
| Lead | 0.060% |
| Mercury | 0.003% |
| City | Population | Air Quality Index | National Avg. |
| Libby, MT | 2,842 | 37 | 26.0% |
| White Haven, MT | 635 | 37 | 26.0% |
| Pioneer Junction, MT | 913 | 37 | 26.0% |
| City | Population | Air Quality Index | National Avg. |
| Darlington, IN | 913 | 42 | 16.0% |
| Midway borough, PA | 913 | 42 | 16.0% |
| Middleton, TN | 913 | 27 | 46.0% |
| Hilshire Village, TX | 913 | 52 | 4.0% |
| Dayton, WY | 913 | 39 | 22.0% |
| Pioneer Junction, MT | 913 | 37 | 26.0% |