| Month | Temp. (min) | Temp. (max) | Temp. (avg) | Precipitation |
| January | 8°F | 34°F | 20°F | 0.5" |
| February | 11°F | 36°F | 22°F | 0.5" |
| March | 22°F | 50°F | 34°F | 0.5" |
| April | 31°F | 60°F | 44°F | 1.2" |
| May | 40°F | 70°F | 54°F | 2.8" |
| June | 49°F | 80°F | 64°F | 2.3" |
| July | 56°F | 91°F | 74°F | 1.3" |
| August | 53°F | 89°F | 70°F | 1.6" |
| September | 43°F | 78°F | 59°F | 1.0" |
| October | 32°F | 61°F | 45°F | 1.3" |
| November | 19°F | 47°F | 32°F | 0.6" |
| December | 6°F | 32°F | 18°F | 0.6" |
| Index | Jordan | Montana | National |
| Air quality index | 21 | 34 | 42 |
| Pollution index | 192,968 | 834,473 | 2,726,193 |
| Measurement | Total |
| Days measured | 362 |
| Days with good air quality | 357 |
| Days with moderate air quality | 4 |
| Days w/ poor A.Q. for sensitive groups | 0 |
| Days with unhealthy air quality | 1 |
| Pollutant | Total |
| Arsenic | 0.000% |
| Benzene | 0.002% |
| Carbon Tetrachloride | 0.000% |
| Lead | 0.000% |
| Mercury | 0.000% |
| City | Population | Air Quality Index | National Avg. |
| Jordan, MT | 428 | 21 | 58.0% |
| City | Population | Air Quality Index | National Avg. |
| Tyonek, AK | 428 | 31 | 38.0% |
| Newville, AL | 428 | 35 | 30.0% |
| Thomaston, AL | 428 | 36 | 28.0% |
| Fulton, CA | 428 | 34 | 32.0% |
| Rio Oso, CA | 428 | 44 | 12.0% |
| Jordan, MT | 428 | 21 | 58.0% |