| 2023 Hardiness Zone: | Zone 6b: -5°F to 0°F Zone 7a: 0°F to 5°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. 21 - Oct. 31 |
| Average Last Frost Date: | May 1 - May 10 |
| Koppen-Geiger Climate Zone: | Dfa - Humid Continental Hot Summers |
| Ecoregion: | 70a - Permian Hills |
| Heat Zone Days: | 8 - 14 days Over 86°F |
Annual Climate Data for ZIP Code 45750 - Marietta, OH | Jan | Feb | Mar | Apr | May | Jun | Jul | Aug | Sep | Oct | Nov | Dec | Annual |
|---|---|---|---|---|---|---|---|---|---|---|---|---|---|
| Avg Min Temp (°F) | 21 | 23 | 31 | 40 | 50 | 59 | 64 | 62 | 55 | 42 | 34 | 26 | 42 |
| Avg Max Temp (°F) | 39 | 43 | 54 | 65 | 74 | 81 | 85 | 83 | 77 | 66 | 54 | 44 | 64 |
| Avg Precip (In.) | 2.84 | 2.75 | 3.64 | 3.21 | 4.1 | 4.21 | 4.29 | 4.03 | 3.19 | 2.71 | 3.15 | 3.17 | 41.29 |