| Month | Temp. (min) | Temp. (max) | Temp. (avg) | Precipitation |
| January | 9°F | 29°F | 18°F | 0.7" |
| February | 10°F | 31°F | 19°F | 1.0" |
| March | 22°F | 46°F | 32°F | 1.1" |
| April | 32°F | 59°F | 44°F | 3.5" |
| May | 43°F | 70°F | 55°F | 7.0" |
| June | 52°F | 80°F | 65°F | 5.2" |
| July | 59°F | 88°F | 72°F | 3.7" |
| August | 56°F | 86°F | 69°F | 3.6" |
| September | 46°F | 76°F | 59°F | 3.6" |
| October | 34°F | 59°F | 45°F | 2.2" |
| November | 20°F | 43°F | 30°F | 1.0" |
| December | 8°F | 27°F | 17°F | 0.8" |
| Index | Culbertson | Montana | National |
| Air quality index | 34 | 34 | 42 |
| Pollution index | 563,599 | 834,473 | 2,726,193 |
| Measurement | Total |
| Days measured | 365 |
| Days with good air quality | 309 |
| Days with moderate air quality | 53 |
| Days w/ poor A.Q. for sensitive groups | 3 |
| Days with unhealthy air quality | 0 |
| Pollutant | Total |
| Arsenic | 0.000% |
| Benzene | 0.010% |
| Carbon Tetrachloride | 0.001% |
| Lead | 0.010% |
| Mercury | 0.000% |
| City | Population | Air Quality Index | National Avg. |
| Froid, MT | 400 | 34 | 32.0% |
| Bainville, MT | 164 | 34 | 32.0% |
| Culbertson, MT | 687 | 34 | 32.0% |
| City | Population | Air Quality Index | National Avg. |
| Glen St. Mary, FL | 687 | 38 | 24.0% |
| Kennard, IN | 687 | 28 | 44.0% |
| Loch Lloyd, MO | 687 | 47 | 6.0% |
| Lakota, ND | 687 | 33 | 34.0% |
| Beach City, OH | 687 | 46 | 8.0% |
| Culbertson, MT | 687 | 34 | 32.0% |