| 2023 Hardiness Zone: | Zone 6a: -10°F to -5°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 1b: -15F to -10F | |
| Average First Frost Date: | Aug. 21 - Aug. 31 | |
| Average Last Frost Date: | Jun. 21 - Jun. 30 | |
| Koppen-Geiger Climate Zone: | Dfb - Humid Continental Mild Summer, Wet All Year | |
| Ecoregion: | 15a - Grave Creek Range-Nine Mile Divide | |
| Current Drought Status: | Exceptional Drought | |
| Heat Zone Days: | 15 - 30 days Over 86°F |
Annual Climate Data for ZIP Code 59820 - Alberton, MT | Jan | Feb | Mar | Apr | May | Jun | Jul | Aug | Sep | Oct | Nov | Dec | Annual |
|---|---|---|---|---|---|---|---|---|---|---|---|---|---|
| Avg Min Temp (°F) | 17 | 20 | 25 | 30 | 37 | 43 | 47 | 47 | 39 | 31 | 24 | 17 | 31 |
| Avg Max Temp (°F) | 32 | 39 | 48 | 57 | 66 | 73 | 82 | 83 | 72 | 58 | 39 | 31 | 57 |
| Avg Precip (In.) | 1.39 | 1.08 | 1.07 | 1.12 | 1.71 | .83 | .99 | 1.26 | .57 | 1.08 | 1.52 | 1.51 | 14.12 |