| 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. 11 - Oct. 20 |
| Average Last Frost Date: | May 1 - May 10 |
| Koppen-Geiger Climate Zone: | Dfa - Humid Continental Hot Summers |
| Ecoregion: | 61c - Low Lime Drift Plain |
| Heat Zone Days: | Rare Over 86°F |
Annual Climate Data for ZIP Code 43334 - Marengo, OH | Jan | Feb | Mar | Apr | May | Jun | Jul | Aug | Sep | Oct | Nov | Dec | Annual |
|---|---|---|---|---|---|---|---|---|---|---|---|---|---|
| Avg Min Temp (°F) | 16 | 19 | 28 | 36 | 48 | 57 | 61 | 59 | 51 | 40 | 31 | 22 | 39 |
| Avg Max Temp (°F) | 33 | 37 | 48 | 60 | 71 | 80 | 83 | 82 | 75 | 63 | 49 | 38 | 60 |
| Avg Precip (In.) | 2.51 | 2.14 | 2.82 | 3.53 | 4.13 | 4.38 | 4.27 | 3.85 | 3.21 | 2.56 | 3.3 | 2.94 | 39.63 |