Chester, Iowa has a Humid Continental Hot Summers With Year Around Precipitation climate (Köppen classification: Dfa). Average annual temperatures range from 34.7 °F (low) to 54.5 °F (high). Annual precipitation averages 35.4 Inches. Chester is located in USDA Plant Hardiness Zone 4b. The growing season typically runs from the last frost around May 1 - May 10 through the first frost around Oct. 1 - Oct. 10.
| Month | Avg. Low | Avg. High | Avg. Precip |
|---|---|---|---|
| January | 6.2 °F | 23.2 °F | 0.85 in. |
| February | 10.1 °F | 27.6 °F | 0.94 in. |
| March | 22.0 °F | 40.3 °F | 1.74 in. |
| April | 33.9 °F | 55.5 °F | 3.74 in. |
| May | 46.1 °F | 67.8 °F | 4.59 in. |
| June | 56.6 °F | 77.4 °F | 5.98 in. |
| July | 59.9 °F | 80.8 °F | 4.3 in. |
| August | 57.4 °F | 78.7 °F | 4.15 in. |
| September | 49.0 °F | 72.4 °F | 3.61 in. |
| October | 36.8 °F | 58.9 °F | 2.69 in. |
| November | 24.8 °F | 42.6 °F | 1.64 in. |
| December | 13.2 °F | 28.9 °F | 1.21 in. |
| Annual | 34.7 °F | 54.5 °F | 35.44 in. |
| Average First Frost Date | Oct. 1 - Oct. 10 |
| Average Last Frost Date | May 1 - May 10 |
| Average Days With Frost | 150-180 Days |
| Plant Hardiness Zone | Zone 4b : -25°F to -20°F |
| Plant Hardiness Zone - 2012 | Zone 4b : -25°F to -20°F |
| Current Drought Conditions | Abnormally Dry |
| Köppen Climate Classification | Dfa - Humid Continental Hot Summers With Year Around Precipitation |