Butler, Pennsylvania has a Humid Continental Hot Summers With Year Around Precipitation climate (Köppen classification: Dfa). Average annual temperatures range from 40.1 °F (low) to 61.3 °F (high). Annual precipitation averages 42.9 Inches. Butler is located in USDA Plant Hardiness Zone 6b. 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 | 19.7 °F | 36.2 °F | 3.31 in. |
| February | 20.6 °F | 39.3 °F | 2.54 in. |
| March | 27.5 °F | 48.5 °F | 3.24 in. |
| April | 37.3 °F | 62.0 °F | 3.79 in. |
| May | 47.8 °F | 72.1 °F | 3.85 in. |
| June | 56.9 °F | 80.0 °F | 4.32 in. |
| July | 60.9 °F | 83.7 °F | 4.2 in. |
| August | 59.4 °F | 82.5 °F | 3.91 in. |
| September | 52.5 °F | 76.1 °F | 3.89 in. |
| October | 41.5 °F | 63.6 °F | 3.26 in. |
| November | 32.3 °F | 51.4 °F | 3.33 in. |
| December | 25.2 °F | 40.7 °F | 3.23 in. |
| Annual | 40.1 °F | 61.3 °F | 42.87 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 6b : -5°F to 0°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 |