Webster City, Iowa has a Humid Continental Hot Summers With Year Around Precipitation climate (Köppen classification: Dfa). Average annual temperatures range from 36.8 °F (low) to 57.9 °F (high). Annual precipitation averages 35.9 Inches. Webster City is located in USDA Plant Hardiness Zone 5a. 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 | 8.7 °F | 26.7 °F | 0.9 in. |
| February | 12.8 °F | 31.2 °F | 1.09 in. |
| March | 24.8 °F | 44.3 °F | 2.01 in. |
| April | 35.9 °F | 59.6 °F | 3.72 in. |
| May | 48.0 °F | 70.8 °F | 5.04 in. |
| June | 58.7 °F | 80.5 °F | 5.47 in. |
| July | 62.2 °F | 83.6 °F | 4.2 in. |
| August | 59.6 °F | 81.4 °F | 4.5 in. |
| September | 50.9 °F | 75.6 °F | 3.29 in. |
| October | 38.3 °F | 62.7 °F | 2.65 in. |
| November | 26.0 °F | 45.9 °F | 1.65 in. |
| December | 15.1 °F | 32.2 °F | 1.39 in. |
| Annual | 36.8 °F | 57.9 °F | 35.91 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 5a : -20°F to -15°F |
| Plant Hardiness Zone - 2012 | Zone 5a : -20°F to -15°F |
| Current Drought Conditions | Abnormally Dry |
| Köppen Climate Classification | Dfa - Humid Continental Hot Summers With Year Around Precipitation |