Dubuque, Iowa has a Humid Continental Hot Summers With Year Around Precipitation climate (Köppen classification: Dfa). Average annual temperatures range from 38.8 °F (low) to 58.1 °F (high). Annual precipitation averages 38.3 Inches. Dubuque is located in USDA Plant Hardiness Zone 5a. The growing season typically runs from the last frost around Apr. 11 - Apr. 20 through the first frost around Oct. 21 - Oct. 31.
| Month | Avg. Low | Avg. High | Avg. Precip |
|---|---|---|---|
| January | 11.3 °F | 27.8 °F | 1.29 in. |
| February | 14.3 °F | 32.2 °F | 1.49 in. |
| March | 26.2 °F | 45.1 °F | 2.08 in. |
| April | 37.8 °F | 58.8 °F | 3.83 in. |
| May | 49.2 °F | 70.9 °F | 4.5 in. |
| June | 59.8 °F | 80.5 °F | 5.68 in. |
| July | 63.6 °F | 83.7 °F | 4.97 in. |
| August | 61.5 °F | 81.8 °F | 3.93 in. |
| September | 53.1 °F | 75.0 °F | 3.7 in. |
| October | 41.2 °F | 61.6 °F | 2.86 in. |
| November | 29.2 °F | 46.0 °F | 2.25 in. |
| December | 17.9 °F | 33.3 °F | 1.71 in. |
| Annual | 38.8 °F | 58.1 °F | 38.29 in. |
| Average First Frost Date | Oct. 21 - Oct. 31 |
| Average Last Frost Date | Apr. 11 - Apr. 20 |
| 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 | Normal |
| Köppen Climate Classification | Dfa - Humid Continental Hot Summers With Year Around Precipitation |