| 2023 Hardiness Zone: | Zone 5a: -20°F to -15°F |
| 2012 Hardiness Zone: | Zone 4b: -25°F to -20°F |
| 1990 Hardiness Zone: | Zone 4a: -30F to -25F |
| Average First Frost Date: | Oct. 1 - Oct. 10 |
| Average Last Frost Date: | May 1 - May 10 |
| Koppen-Geiger Climate Zone: | Dfb - Humid Continental Mild Summer, Wet All Year |
| Ecoregion: | 47g - Lower St. Croix and Vermillion Valleys |
| Heat Zone Days: | 1 - 7 days Over 86°F |
Annual Climate Data for ZIP Code 55001 - Afton, MN | Jan | Feb | Mar | Apr | May | Jun | Jul | Aug | Sep | Oct | Nov | Dec | Annual |
|---|---|---|---|---|---|---|---|---|---|---|---|---|---|
| Avg Min Temp (°F) | 3 | 10 | 22 | 35 | 47 | 56 | 61 | 59 | 50 | 38 | 25 | 10 | 35 |
| Avg Max Temp (°F) | 22 | 29 | 41 | 58 | 71 | 79 | 83 | 81 | 72 | 60 | 41 | 27 | 55 |
| Avg Precip (In.) | .95 | .72 | 1.76 | 2.68 | 3.51 | 4.5 | 4.39 | 4.45 | 3.36 | 2.38 | 1.98 | .93 | 31.63 |