| 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 5b: -15°F to -10°F |
| 1990 Hardiness Zone: | Zone 5a: -20F to -15F |
| 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: | 55b - Loamy High Lime Till Plains |
| Heat Zone Days: | 8 - 14 days Over 86°F |
Annual Climate Data for ZIP Code 46278 - Indianapolis, IN | Jan | Feb | Mar | Apr | May | Jun | Jul | Aug | Sep | Oct | Nov | Dec | Annual |
|---|---|---|---|---|---|---|---|---|---|---|---|---|---|
| Avg Min Temp (°F) | 18 | 22 | 31 | 40 | 51 | 60 | 64 | 62 | 54 | 43 | 34 | 23 | 42 |
| Avg Max Temp (°F) | 34 | 40 | 51 | 63 | 73 | 82 | 85 | 84 | 78 | 66 | 51 | 39 | 62 |
| Avg Precip (In.) | 2.36 | 2.32 | 3.29 | 3.81 | 4.42 | 4.14 | 4.48 | 3.78 | 2.95 | 2.86 | 3.61 | 2.99 | 41 |