| 2023 Hardiness Zone: | Zone 7a: 0°F to 5°F |
| 2012 Hardiness Zone: | Zone 6b: -5°F to 0°F |
| 1990 Hardiness Zone: | Zone 6a: -10F to -5F |
| Average First Frost Date: | Oct. 21 - Oct. 31 |
| Average Last Frost Date: | Apr. 11 - Apr. 20 |
| Koppen-Geiger Climate Zone: | Cfa - Humid Subtropical Climate |
| Ecoregion: | 71n - Southern Shawnee Hills |
| Heat Zone Days: | 61 - 90 days Over 86°F |
Annual Climate Data for ZIP Code 62906 - Anna, IL | Jan | Feb | Mar | Apr | May | Jun | Jul | Aug | Sep | Oct | Nov | Dec | Annual |
|---|---|---|---|---|---|---|---|---|---|---|---|---|---|
| Avg Min Temp (°F) | 23 | 27 | 35 | 45 | 54 | 62 | 66 | 64 | 56 | 45 | 36 | 27 | 45 |
| Avg Max Temp (°F) | 42 | 49 | 59 | 69 | 78 | 86 | 89 | 88 | 81 | 72 | 57 | 46 | 68 |
| Avg Precip (In.) | 3.49 | 3.4 | 4.7 | 4.67 | 5.15 | 4.19 | 3.46 | 3.57 | 3.13 | 3.33 | 4.69 | 4.25 | 48.04 |