Polk, Nebraska has a Humid Continental Hot Summers With Year Around Precipitation climate (Köppen classification: Dfa). Average annual temperatures range from 39.5 °F (low) to 62.2 °F (high). Annual precipitation averages 27.9 Inches. Polk is located in USDA Plant Hardiness Zone 5b. 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 | 14.6 °F | 34.8 °F | 0.64 in. |
| February | 18.2 °F | 38.9 °F | 0.65 in. |
| March | 27.6 °F | 51.2 °F | 1.54 in. |
| April | 37.9 °F | 62.6 °F | 2.75 in. |
| May | 49.7 °F | 72.9 °F | 5.0 in. |
| June | 60.3 °F | 82.7 °F | 3.98 in. |
| July | 64.7 °F | 86.4 °F | 3.54 in. |
| August | 62.3 °F | 84.3 °F | 3.26 in. |
| September | 53.1 °F | 78.4 °F | 2.4 in. |
| October | 40.1 °F | 65.6 °F | 2.12 in. |
| November | 27.4 °F | 50.7 °F | 1.19 in. |
| December | 18.0 °F | 37.9 °F | 0.86 in. |
| Annual | 39.5 °F | 62.2 °F | 27.93 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 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 |