| 2023 Hardiness Zone: | Zone 3b: -35°F to -30°F Zone 4a: -30°F to -25°F | |
| 2012 Hardiness Zone: | Zone 3b: -35°F to -30°F | |
| 1990 Hardiness Zone: | Zone 3b: -35F to -30F | |
| 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: | 48d - Lake Agassiz Plains | |
| Current Drought Status: | Exceptional Drought | |
| Heat Zone Days: | Rare Over 86°F |
Annual Climate Data for ZIP Code 56557 - Mahnomen, MN | Jan | Feb | Mar | Apr | May | Jun | Jul | Aug | Sep | Oct | Nov | Dec | Annual |
|---|---|---|---|---|---|---|---|---|---|---|---|---|---|
| Avg Min Temp (°F) | -8 | 0 | 14 | 29 | 43 | 52 | 56 | 54 | 43 | 31 | 16 | 0 | 27 |
| Avg Max Temp (°F) | 14 | 22 | 34 | 52 | 67 | 75 | 79 | 79 | 68 | 54 | 34 | 19 | 50 |
| Avg Precip (In.) | .88 | .64 | 1.08 | 1.44 | 2.56 | 4.15 | 3.35 | 3.18 | 2.45 | 2.19 | 1.05 | .66 | 23.63 |