| 2023 Hardiness Zone: | Zone 6a: -10°F to -5°F |
| 2012 Hardiness Zone: | Zone 6a: -10°F to -5°F Zone 5b: -15°F to -10°F |
| 1990 Hardiness Zone: | Zone 1b: -15F to -10F |
| Average First Frost Date: | Oct. 21 - Oct. 31 |
| Average Last Frost Date: | May 1 - May 10 |
| Koppen-Geiger Climate Zone: | Dfa - Humid Continental Hot Summers |
| Ecoregion: | 56b - Elkhart Till Plains |
| Heat Zone Days: | Rare Over 86°F |
Annual Climate Data for ZIP Code 46365 - Mill Creek, IN | Jan | Feb | Mar | Apr | May | Jun | Jul | Aug | Sep | Oct | Nov | Dec | Annual |
|---|---|---|---|---|---|---|---|---|---|---|---|---|---|
| Avg Min Temp (°F) | 15 | 19 | 28 | 38 | 49 | 58 | 63 | 61 | 53 | 42 | 32 | 21 | 40 |
| Avg Max Temp (°F) | 30 | 35 | 46 | 58 | 70 | 80 | 83 | 81 | 74 | 62 | 48 | 35 | 59 |
| Avg Precip (In.) | 2.23 | 1.87 | 2.91 | 3.61 | 3.61 | 4.29 | 3.77 | 3.91 | 3.79 | 3.22 | 3.54 | 3.06 | 39.82 |