| 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 |
| 1990 Hardiness Zone: | Zone 6a: -10F to -5F |
| Average First Frost Date: | Oct. 21 - Oct. 31 |
| Average Last Frost Date: | Apr. 21 - Apr. 30 |
| Koppen-Geiger Climate Zone: | Dfa - Humid Continental Hot Summers |
| Ecoregion: | 55e - Darby Plains |
| Heat Zone Days: | Rare Over 86°F |
Annual Climate Data for ZIP Code 43160 - Washington Court House, OH | Jan | Feb | Mar | Apr | May | Jun | Jul | Aug | Sep | Oct | Nov | Dec | Annual |
|---|---|---|---|---|---|---|---|---|---|---|---|---|---|
| Avg Min Temp (°F) | 20 | 23 | 32 | 41 | 51 | 60 | 64 | 62 | 55 | 44 | 34 | 25 | 43 |
| Avg Max Temp (°F) | 36 | 40 | 51 | 63 | 72 | 80 | 83 | 82 | 76 | 66 | 52 | 40 | 62 |
| Avg Precip (In.) | 2.57 | 2.45 | 3.3 | 3.54 | 4.7 | 3.89 | 3.9 | 3.86 | 2.71 | 2.63 | 3.06 | 2.8 | 39.39 |