| 2023 Hardiness Zone: | Zone 4a: -30°F to -25°F |
| 2012 Hardiness Zone: | Zone 4a: -30°F to -25°F |
| 1990 Hardiness Zone: | Zone 4a: -30F to -25F |
| Average First Frost Date: | Sep. 21 - Sep. 30 |
| Average Last Frost Date: | May 21 - May 31 |
| Koppen-Geiger Climate Zone: | Dfb - Humid Continental Mild Summer, Wet All Year |
| Ecoregion: | 42b - Collapsed Glacial Outwash |
| Heat Zone Days: | 1 - 7 days Over 86°F |
Annual Climate Data for ZIP Code 58504 - Bismarck, ND | Jan | Feb | Mar | Apr | May | Jun | Jul | Aug | Sep | Oct | Nov | Dec | Annual |
|---|---|---|---|---|---|---|---|---|---|---|---|---|---|
| Avg Min Temp (°F) | -1 | 8 | 19 | 31 | 43 | 52 | 57 | 55 | 44 | 32 | 18 | 5 | 30 |
| Avg Max Temp (°F) | 21 | 28 | 40 | 56 | 69 | 77 | 84 | 83 | 71 | 58 | 38 | 25 | 54 |
| Avg Precip (In.) | .45 | .49 | .8 | 1.45 | 2.26 | 2.66 | 2.6 | 2.09 | 1.58 | 1.31 | .68 | .44 | 16.8 |