| 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 Zone 4b: -25°F to -20°F |
| 1990 Hardiness Zone: | Zone 4b: -25F to -20F |
| Average First Frost Date: | Oct. 1 - Oct. 10 |
| Average Last Frost Date: | May 11 - May 20 |
| Koppen-Geiger Climate Zone: | Dfb - Humid Continental Mild Summer, Wet All Year |
| Ecoregion: | 51f - Green Bay Till and Lacustrine Plain |
| Heat Zone Days: | Rare Over 86°F |
Annual Climate Data for ZIP Code 54165 - Seymour, WI | Jan | Feb | Mar | Apr | May | Jun | Jul | Aug | Sep | Oct | Nov | Dec | Annual |
|---|---|---|---|---|---|---|---|---|---|---|---|---|---|
| Avg Min Temp (°F) | 6 | 11 | 21 | 33 | 45 | 54 | 59 | 57 | 48 | 37 | 25 | 12 | 34 |
| Avg Max Temp (°F) | 24 | 29 | 40 | 55 | 69 | 77 | 82 | 79 | 70 | 58 | 42 | 29 | 54 |
| Avg Precip (In.) | 1.29 | 1.02 | 2.03 | 2.69 | 3.05 | 3.59 | 3.59 | 3.86 | 3.3 | 2.32 | 2.27 | 1.4 | 30.4 |