Last frost date in Butte-Silver Bow (balance), Montana
June 13
Average last frost in spring. In an early year (1 in 10) it's over by May 27; in a late year (1 in 10) it comes after July 1.
September 5
Average first frost in fall. 1 year in 10 it comes by August 24.
Source: NOAA U.S. Climate Normals 1991–2020, station Butte Bert Mooney AP (USW00024135), 9 miles from Butte-Silver Bow (balance), elevation 5,506 ft. NOAA National Centers for Environmental Information. These are long-term averages, not a forecast.
| Early year | Average | Late year | |
|---|---|---|---|
| Last frost in spring | May 27 | June 13 | July 1 |
| First frost in fall | Aug 24 | Sept 5 | Sept 19 |
Frost-free days in an average year: 83
| Chance in a year | Average last in spring | Average first in fall | |
|---|---|---|---|
| Light frost (36°F) | Every year | — | — |
| Frost (32°F) | Every year | June 13 | Sept 5 |
| Hard freeze (28°F) | Every year | May 21 | Sept 17 |
Nights at 32°F or colder in an average year: 220
What to plant now in Butte-Silver Bow (balance)
Nothing in USDA's planting table is in its window in Butte-Silver Bow (balance) right now, or opens in the next 45 days.
- Spring planting calendar for an average last frost around June 10 Butte-Silver Bow (balance): June 13
- Fall planting calendar for an average first frost around September 10 Butte-Silver Bow (balance): September 5
Planting dates: USDA Home and Garden Bulletin No. 9 (1967), “Suburban and Farm Vegetable Gardens,” tables 4 and 5. How we match the table.
Nearby in Montana
- Helena 57 mi · last frost May 9
- Belgrade 72 mi · last frost May 26
- Bozeman 79 mi · last frost May 26
- Missoula 94 mi · last frost May 10
- Great Falls 128 mi · last frost May 6
Updated