| 2023 Hardiness Zone: | Zone 5a: -20°F to -15°F Zone 5b: -15°F to -10°F |
| 2012 Hardiness Zone: | Zone 5a: -20°F to -15°F |
| 1990 Hardiness Zone: | Zone 5a: -20F to -15F |
| Average First Frost Date: | Oct. 11 - Oct. 20 |
| Average Last Frost Date: | May 1 - May 10 |
| Koppen-Geiger Climate Zone: | Dfb - Humid Continental Mild Summer, Wet All Year |
| Ecoregion: | 53d - Lake Michigan Lacustrine Clay Plain |
| Heat Zone Days: | Rare Over 86°F |
Annual Climate Data for ZIP Code 54963 - Omro, WI | Jan | Feb | Mar | Apr | May | Jun | Jul | Aug | Sep | Oct | Nov | Dec | Annual |
|---|---|---|---|---|---|---|---|---|---|---|---|---|---|
| Avg Min Temp (°F) | 6 | 11 | 22 | 34 | 46 | 56 | 60 | 58 | 50 | 39 | 27 | 14 | 35 |
| Avg Max Temp (°F) | 24 | 29 | 41 | 55 | 69 | 78 | 82 | 79 | 71 | 59 | 43 | 29 | 55 |
| Avg Precip (In.) | 1.25 | 1.08 | 2.09 | 2.91 | 3.15 | 3.76 | 3.8 | 4.12 | 3.43 | 2.29 | 2.31 | 1.43 | 31.62 |