| 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 6a: -10F to -5F |
| Average First Frost Date: | Nov. 1 - Nov. 10 |
| Average Last Frost Date: | Apr. 11 - Apr. 20 |
| Koppen-Geiger Climate Zone: | Dfa - Humid Continental Hot Summers |
| Ecoregion: | 72f - River Hills |
| Heat Zone Days: | 46 - 60 days Over 86°F |
Annual Climate Data for ZIP Code 62010 - Bethalto, IL | Jan | Feb | Mar | Apr | May | Jun | Jul | Aug | Sep | Oct | Nov | Dec | Annual |
|---|---|---|---|---|---|---|---|---|---|---|---|---|---|
| Avg Min Temp (°F) | 19 | 24 | 33 | 44 | 55 | 64 | 68 | 66 | 57 | 46 | 35 | 24 | 45 |
| Avg Max Temp (°F) | 36 | 42 | 53 | 64 | 75 | 84 | 88 | 86 | 79 | 68 | 53 | 41 | 64 |
| Avg Precip (In.) | 2.1 | 2.2 | 3.48 | 3.91 | 4.22 | 3.71 | 3.7 | 3.38 | 3.14 | 2.78 | 3.73 | 2.91 | 39.25 |