| 2023 Hardiness Zone: | Zone 6a: -10°F to -5°F Zone 6b: -5°F to 0°F |
| 2012 Hardiness Zone: | Zone 6a: -10°F to -5°F Zone 6b: -5°F to 0°F |
| 1990 Hardiness Zone: | Zone 1b: -15F to -10F |
| Average First Frost Date: | Oct. 11 - Oct. 20 |
| Average Last Frost Date: | Apr. 21 - Apr. 30 |
| Koppen-Geiger Climate Zone: | Dfa - Humid Continental Hot Summers |
| Ecoregion: | 39g - Meramec River Hills |
| Heat Zone Days: | 46 - 60 days Over 86°F |
Annual Climate Data for ZIP Code 63664 - Potosi, MO | Jan | Feb | Mar | Apr | May | Jun | Jul | Aug | Sep | Oct | Nov | Dec | Annual |
|---|---|---|---|---|---|---|---|---|---|---|---|---|---|
| Avg Min Temp (°F) | 20 | 25 | 33 | 43 | 51 | 60 | 65 | 62 | 55 | 43 | 34 | 25 | 43 |
| Avg Max Temp (°F) | 41 | 47 | 57 | 69 | 76 | 84 | 89 | 87 | 79 | 70 | 56 | 45 | 67 |
| Avg Precip (In.) | 2.34 | 2.42 | 3.88 | 4.28 | 4.45 | 3.87 | 3.77 | 3.65 | 3.43 | 3.1 | 4.46 | 3.35 | 43 |