Portis, Kansas has a Humid Continental Hot Summers With Year Around Precipitation climate (Köppen classification: Dfa). Average annual temperatures range from 41.3 °F (low) to 66.1 °F (high). Annual precipitation averages 25.3 Inches. Portis is located in USDA Plant Hardiness Zone 6a. The growing season typically runs from the last frost around Apr. 11 - Apr. 20 through the first frost around Oct. 11 - Oct. 20.
| Month | Avg. Low | Avg. High | Avg. Precip |
|---|---|---|---|
| January | 17.3 °F | 39.6 °F | 0.6 in. |
| February | 20.2 °F | 44.5 °F | 0.7 in. |
| March | 29.4 °F | 55.6 °F | 1.4 in. |
| April | 39.3 °F | 65.5 °F | 2.12 in. |
| May | 50.8 °F | 74.9 °F | 3.78 in. |
| June | 61.9 °F | 86.4 °F | 3.54 in. |
| July | 66.7 °F | 91.5 °F | 4.36 in. |
| August | 64.7 °F | 88.7 °F | 3.19 in. |
| September | 55.3 °F | 81.0 °F | 2.21 in. |
| October | 41.7 °F | 69.5 °F | 1.58 in. |
| November | 29.0 °F | 54.0 °F | 1.02 in. |
| December | 19.7 °F | 42.3 °F | 0.84 in. |
| Annual | 41.3 °F | 66.1 °F | 25.34 in. |
| Average First Frost Date | Oct. 11 - Oct. 20 |
| Average Last Frost Date | Apr. 11 - Apr. 20 |
| Average Days With Frost | 125-150 Days |
| Plant Hardiness Zone | Zone 6a : -10°F to -5°F |
| Plant Hardiness Zone - 2012 | Zone 6a : -10°F to -5°F |
| Current Drought Conditions | Normal |
| Köppen Climate Classification | Dfa - Humid Continental Hot Summers With Year Around Precipitation |