| 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 Zone 4a: -30°F to -25°F | |
| 1990 Hardiness Zone: | Zone 3a: -40F to -35F | |
| Average First Frost Date: | Sep. 21 - Sep. 30 | |
| Average Last Frost Date: | Jun. 1 - Jun. 10 | |
| Koppen-Geiger Climate Zone: | Dfb - Humid Continental Mild Summer, Wet All Year | |
| Ecoregion: | 50m - Mesabi Range | |
| Current Drought Status: | Exceptional Drought | |
| Heat Zone Days: | Rare Over 86°F |
Annual Climate Data for ZIP Code 55768 - Mountain Iron, MN | Jan | Feb | Mar | Apr | May | Jun | Jul | Aug | Sep | Oct | Nov | Dec | Annual |
|---|---|---|---|---|---|---|---|---|---|---|---|---|---|
| Avg Min Temp (°F) | -6 | 1 | 13 | 27 | 39 | 48 | 53 | 51 | 43 | 32 | 17 | 2 | 26 |
| Avg Max Temp (°F) | 16 | 24 | 36 | 51 | 66 | 74 | 77 | 75 | 64 | 52 | 33 | 21 | 49 |
| Avg Precip (In.) | .88 | .57 | 1.1 | 1.63 | 2.74 | 4.54 | 4.02 | 3.79 | 3.4 | 2.48 | 1.44 | .72 | 27.3 |