Bradford, Illinois has a Humid Continental Hot Summers With Year Around Precipitation climate (Köppen classification: Dfa). Average annual temperatures range from 39.2 °F (low) to 59 °F (high). Annual precipitation averages 38.1 Inches. Bradford is located in USDA Plant Hardiness Zone 5b. The growing season typically runs from the last frost around Apr. 11 - Apr. 20 through the first frost around Oct. 11 - Oct. 20.
| Month | Avg. Low | Avg. High | Avg. Precip |
|---|---|---|---|
| January | 13.7 °F | 29.9 °F | 1.85 in. |
| February | 16.9 °F | 34.3 °F | 1.93 in. |
| March | 27.1 °F | 47.1 °F | 2.35 in. |
| April | 37.9 °F | 59.7 °F | 3.71 in. |
| May | 49.8 °F | 70.7 °F | 4.73 in. |
| June | 59.6 °F | 79.6 °F | 4.52 in. |
| July | 62.8 °F | 82.7 °F | 4.11 in. |
| August | 60.5 °F | 81.3 °F | 3.84 in. |
| September | 52.1 °F | 75.7 °F | 3.58 in. |
| October | 40.7 °F | 63.1 °F | 2.88 in. |
| November | 29.4 °F | 48.3 °F | 2.57 in. |
| December | 19.4 °F | 35.4 °F | 2.06 in. |
| Annual | 39.2 °F | 59 °F | 38.13 in. |
| Average First Frost Date | Oct. 11 - Oct. 20 |
| Average Last Frost Date | Apr. 11 - Apr. 20 |
| Average Days With Frost | 125-150 Days |
| Plant Hardiness Zone | Zone 5b : -15°F to -10°F |
| Plant Hardiness Zone - 2012 | Zone 5b : -15°F to -10°F |
| Current Drought Conditions | Normal |
| Köppen Climate Classification | Dfa - Humid Continental Hot Summers With Year Around Precipitation |