| 2023 Hardiness Zone: | Zone 5a: -20°F to -15°F Zone 4b: -25°F to -20°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: | 51a - St. Croix Outwash Plain |
| Heat Zone Days: | 1 - 7 days Over 86°F |
Annual Climate Data for ZIP Code 55082 - Stillwater, MN | Jan | Feb | Mar | Apr | May | Jun | Jul | Aug | Sep | Oct | Nov | Dec | Annual |
|---|---|---|---|---|---|---|---|---|---|---|---|---|---|
| Avg Min Temp (°F) | 4 | 10 | 23 | 35 | 48 | 57 | 62 | 60 | 51 | 39 | 25 | 11 | 35 |
| Avg Max Temp (°F) | 23 | 30 | 41 | 58 | 71 | 80 | 84 | 81 | 72 | 60 | 41 | 27 | 56 |
| Avg Precip (In.) | 1.01 | .73 | 1.79 | 2.78 | 3.54 | 4.71 | 4.57 | 4.73 | 3.48 | 2.54 | 2.1 | .93 | 32.9 |