| Month | Temp. (min) | Temp. (max) | Temp. (avg) | Precipitation |
| January | 15°F | 35°F | 25°F | 1.2" |
| February | 23°F | 44°F | 32°F | 0.6" |
| March | 25°F | 51°F | 37°F | 1.2" |
| April | 31°F | 57°F | 43°F | 2.1" |
| May | 38°F | 66°F | 51°F | 4.2" |
| June | 49°F | 77°F | 63°F | 3.5" |
| July | 54°F | 87°F | 71°F | 3.1" |
| August | 52°F | 85°F | 68°F | 3.7" |
| September | 46°F | 75°F | 59°F | 4.6" |
| October | 35°F | 60°F | 46°F | 4.2" |
| November | 24°F | 47°F | 35°F | 2.0" |
| December | 16°F | 37°F | 26°F | 1.8" |
| Index | Grass Range | Montana | National |
| Air quality index | 21 | 34 | 42 |
| Pollution index | 231,483 | 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 | 0.001% |
| Carbon Tetrachloride | 0.000% |
| Lead | 0.000% |
| Mercury | 0.000% |
| City | Population | Air Quality Index | National Avg. |
| Grass Range, MT | 121 | 21 | 58.0% |
| City | Population | Air Quality Index | National Avg. |
| Alcan Border, AK | 121 | 38 | 24.0% |
| Tenakee Springs, AK | 121 | 20 | 60.0% |
| Providence, AL | 121 | 36 | 28.0% |
| Rondo, AR | 121 | 45 | 10.0% |
| Pine Level, FL | 121 | 41 | 18.0% |
| Grass Range, MT | 121 | 21 | 58.0% |
Here are the best places to live in Montana
10 best cities to buy a new house in Montana
10 Best cities in Montana for employment
Top 10 cities in Montana with the best education system