| 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 6b: -5F to 0F |
| Average First Frost Date: | Oct. 11 - Oct. 20 |
| Average Last Frost Date: | May 11 - May 20 |
| Koppen-Geiger Climate Zone: | Dfa - Humid Continental Hot Summers |
| Ecoregion: | 56d - Michigan Lake Plain |
| Heat Zone Days: | Rare Over 86°F |
Annual Climate Data for ZIP Code 49085 - Saint Joseph, MI | Jan | Feb | Mar | Apr | May | Jun | Jul | Aug | Sep | Oct | Nov | Dec | Annual |
|---|---|---|---|---|---|---|---|---|---|---|---|---|---|
| Avg Min Temp (°F) | 18 | 20 | 28 | 37 | 46 | 56 | 61 | 59 | 52 | 42 | 33 | 23 | 39 |
| Avg Max Temp (°F) | 31 | 35 | 45 | 57 | 68 | 77 | 81 | 80 | 73 | 62 | 48 | 35 | 58 |
| Avg Precip (In.) | 2.29 | 1.68 | 2.44 | 3.68 | 3.34 | 3.54 | 3.29 | 3.53 | 4.14 | 3.1 | 3.32 | 2.75 | 37.09 |