Irvington, Iowa has a Humid Continental Hot Summers With Year Around Precipitation climate (Köppen classification: Dfa). Average annual temperatures range from 36.6 °F (low) to 56.4 °F (high). Annual precipitation averages 34.1 Inches. Irvington is located in USDA Plant Hardiness Zone 5a. The growing season typically runs from the last frost around Apr. 21 - Apr. 30 through the first frost around Oct. 1 - Oct. 10.
| Month | Avg. Low | Avg. High | Avg. Precip |
|---|---|---|---|
| January | 8.1 °F | 25.0 °F | 0.81 in. |
| February | 12.3 °F | 29.4 °F | 0.99 in. |
| March | 24.3 °F | 42.4 °F | 1.96 in. |
| April | 35.7 °F | 57.8 °F | 3.64 in. |
| May | 48.3 °F | 69.6 °F | 4.73 in. |
| June | 59.3 °F | 79.6 °F | 5.3 in. |
| July | 62.5 °F | 82.5 °F | 4.18 in. |
| August | 59.7 °F | 80.2 °F | 4.14 in. |
| September | 50.8 °F | 74.4 °F | 3.2 in. |
| October | 38.2 °F | 61.2 °F | 2.34 in. |
| November | 25.7 °F | 44.4 °F | 1.56 in. |
| December | 14.4 °F | 30.4 °F | 1.2 in. |
| Annual | 36.6 °F | 56.4 °F | 34.05 in. |
| Average First Frost Date | Oct. 1 - Oct. 10 |
| Average Last Frost Date | Apr. 21 - Apr. 30 |
| Average Days With Frost | 125-150 Days |
| Plant Hardiness Zone | Zone 5a : -20°F to -15°F |
| Plant Hardiness Zone - 2012 | Zone 5a : -20°F to -15°F |
| Current Drought Conditions | Moderate Drought |
| Köppen Climate Classification | Dfa - Humid Continental Hot Summers With Year Around Precipitation |