| 2023 Hardiness Zone: | Zone 6a: -10°F to -5°F Zone 6b: -5°F to 0°F Zone 5b: -15°F to -10°F | |
| 2012 Hardiness Zone: | Zone 6a: -10°F to -5°F Zone 5a: -20°F to -15°F Zone 5b: -15°F to -10°F | |
| 1990 Hardiness Zone: | Zone 4b: -25F to -20F | |
| Average First Frost Date: | Sep. 21 - Sep. 30 | |
| Average Last Frost Date: | May 11 - May 20 | |
| Koppen-Geiger Climate Zone: | Dfb - Humid Continental Mild Summer, Wet All Year | |
| Ecoregion: | 15l - Salish Mountains | |
| Current Drought Status: | Exceptional Drought | |
| Heat Zone Days: | 1 - 7 days Over 86°F |
Annual Climate Data for ZIP Code 59931 - Rollins, MT | Jan | Feb | Mar | Apr | May | Jun | Jul | Aug | Sep | Oct | Nov | Dec | Annual |
|---|---|---|---|---|---|---|---|---|---|---|---|---|---|
| Avg Min Temp (°F) | 17 | 21 | 26 | 32 | 39 | 46 | 50 | 50 | 41 | 33 | 26 | 19 | 33 |
| Avg Max Temp (°F) | 31 | 37 | 45 | 56 | 65 | 73 | 81 | 81 | 70 | 56 | 40 | 32 | 56 |
| Avg Precip (In.) | 1.61 | 1.25 | 1.38 | 1.53 | 2.64 | 2.38 | 1.61 | 1.34 | 1.49 | 1.23 | 1.75 | 1.84 | 20.04 |