| 2023 Hardiness Zone: | Zone 5a: -20°F to -15°F Zone 4b: -25°F to -20°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: | 52b - Paleozoic Plateau/Coulee Section | |
| Current Drought Status: | Exceptional Drought | |
| Heat Zone Days: | Rare Over 86°F |
Annual Climate Data for ZIP Code 52175 - West Union, IA | Jan | Feb | Mar | Apr | May | Jun | Jul | Aug | Sep | Oct | Nov | Dec | Annual |
|---|---|---|---|---|---|---|---|---|---|---|---|---|---|
| Avg Min Temp (°F) | 5 | 11 | 23 | 35 | 47 | 56 | 60 | 58 | 49 | 37 | 25 | 12 | 35 |
| Avg Max Temp (°F) | 24 | 30 | 43 | 58 | 70 | 79 | 83 | 80 | 73 | 61 | 42 | 29 | 56 |
| Avg Precip (In.) | 1.05 | 1.08 | 2.06 | 3.57 | 4.17 | 4.62 | 4.3 | 4.85 | 3.3 | 2.47 | 2.3 | 1.32 | 35.09 |