| 2023 Hardiness Zone: | Zone 3b: -35°F to -30°F Zone 4b: -25°F to -20°F Zone 4a: -30°F to -25°F | |
| 2012 Hardiness Zone: | Zone 3b: -35°F to -30°F Zone 4a: -30°F to -25°F | |
| 1990 Hardiness Zone: | Zone 3b: -35F to -30F | |
| Average First Frost Date: | Sep.11 - Sep. 20 | |
| Average Last Frost Date: | Jun. 1 - Jun. 10 | |
| Koppen-Geiger Climate Zone: | BSk - Cold Semi-Arid Climate | |
| Ecoregion: | 42i - Glaciated Dark Brown Prairie | |
| Current Drought Status: | Exceptional Drought | |
| Heat Zone Days: | 15 - 30 days Over 86°F |
Annual Climate Data for ZIP Code 59218 - Culbertson, MT | Jan | Feb | Mar | Apr | May | Jun | Jul | Aug | Sep | Oct | Nov | Dec | Annual |
|---|---|---|---|---|---|---|---|---|---|---|---|---|---|
| Avg Min Temp (°F) | -1 | 8 | 19 | 30 | 42 | 50 | 54 | 53 | 42 | 31 | 16 | 4 | 29 |
| Avg Max Temp (°F) | 22 | 31 | 44 | 60 | 72 | 80 | 86 | 86 | 73 | 60 | 39 | 26 | 56 |
| Avg Precip (In.) | .32 | .24 | .5 | .94 | 2.09 | 2.81 | 2.29 | 1.28 | 1.52 | .84 | .46 | .38 | 13.68 |