Click on a day for an hourly weather forecast
The temperatures in Montana in August are comfortable with low of 15°C and and high up to 29°C.
You can expect up to 3 rainy days in Montana during the month of August.
Our weather forecast can give you a great sense of what weather to expect in Montana in August 2025.
If you’re planning to visit Montana in the near future, we highly recommend that you review the 14 day weather forecast for Montana before you arrive.
| Month | Temperatures | Rainy Days | Dry Days | Snowy Days | Rainfall | Weather | More details |
|---|---|---|---|---|---|---|---|
| January | 0° / -8° | 4 | 13 | 14 | 31 mm | Awful | Montana in January |
| February | 0° / -9° | 4 | 10 | 15 | 37 mm | Awful | Montana in February |
| March | 8° / -3° | 5 | 15 | 11 | 51 mm | Bad | Montana in March |
| April | 12° / 1° | 6 | 17 | 7 | 74 mm | Bad | Montana in April |
| May | 18° / 6° | 8 | 22 | 1 | 92 mm | Ok | Montana in May |
| June | 25° / 10° | 5 | 25 | 0 | 62 mm | Perfect | Montana in June |
| July | 31° / 15° | 2 | 29 | 0 | 29 mm | Good | Montana in July |
| August | 29° / 15° | 2 | 29 | 0 | 42 mm | Good | Montana in August |
| September | 24° / 10° | 2 | 28 | 0 | 34 mm | Perfect | Montana in September |
| October | 14° / 3° | 3 | 24 | 4 | 57 mm | Ok | Montana in October |
| November | 7° / -3° | 4 | 18 | 8 | 31 mm | Bad | Montana in November |
| December | 0° / -8° | 5 | 11 | 14 | 28 mm | Awful | Montana in December |