Karns City, Pennsylvania has a Humid Continental Hot Summers With Year Around Precipitation climate (Köppen classification: Dfa). Average annual temperatures range from 38.9 °F (low) to 60.7 °F (high). Annual precipitation averages 44.5 Inches. Karns City is located in USDA Plant Hardiness Zone 6a. The growing season typically runs from the last frost around May 11 - May 20 through the first frost around Oct. 11 - Oct. 20.
| Month | Avg. Low | Avg. High | Avg. Precip |
|---|---|---|---|
| January | 18.2 °F | 35.0 °F | 3.36 in. |
| February | 19.2 °F | 38.1 °F | 2.59 in. |
| March | 26.2 °F | 47.5 °F | 3.3 in. |
| April | 36.4 °F | 61.7 °F | 3.97 in. |
| May | 46.7 °F | 72.1 °F | 3.82 in. |
| June | 55.5 °F | 79.7 °F | 5.1 in. |
| July | 59.3 °F | 83.1 °F | 4.54 in. |
| August | 58.0 °F | 82.3 °F | 3.82 in. |
| September | 51.0 °F | 75.8 °F | 4.06 in. |
| October | 40.3 °F | 63.5 °F | 3.26 in. |
| November | 31.6 °F | 50.3 °F | 3.3 in. |
| December | 24.1 °F | 39.4 °F | 3.42 in. |
| Annual | 38.9 °F | 60.7 °F | 44.54 in. |
| Average First Frost Date | Oct. 11 - Oct. 20 |
| Average Last Frost Date | May 11 - May 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 |