| 2023 Hardiness Zone: | Zone 4b: -25°F to -20°F Zone 4a: -30°F to -25°F |
| 2012 Hardiness Zone: | Zone 4a: -30°F to -25°F |
| 1990 Hardiness Zone: | Zone 3b: -35F to -30F |
| Average First Frost Date: | Oct. 1 - Oct. 10 |
| Average Last Frost Date: | May 11 - May 20 |
| Koppen-Geiger Climate Zone: | Dfb - Humid Continental Mild Summer, Wet All Year |
| Ecoregion: | 46c - Glacial Lake Basins |
| Heat Zone Days: | 1 - 7 days Over 86°F |
Annual Climate Data for ZIP Code 57430 - Britton, SD | Jan | Feb | Mar | Apr | May | Jun | Jul | Aug | Sep | Oct | Nov | Dec | Annual |
|---|---|---|---|---|---|---|---|---|---|---|---|---|---|
| Avg Min Temp (°F) | -1 | 7 | 19 | 32 | 45 | 54 | 59 | 57 | 47 | 35 | 19 | 5 | 31 |
| Avg Max Temp (°F) | 20 | 28 | 40 | 57 | 71 | 79 | 84 | 83 | 73 | 60 | 38 | 25 | 55 |
| Avg Precip (In.) | .62 | .51 | 1.05 | 1.74 | 2.83 | 3.45 | 3.24 | 2.3 | 2.05 | 1.62 | .82 | .37 | 20.6 |