New Washington, Pennsylvania has a Humid Continental Mild Summer, Wet All Year climate (Köppen classification: Dfb). Average annual temperatures range from 37.7 °F (low) to 57.8 °F (high). Annual precipitation averages 47.8 Inches. New Washington 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. 1 - Oct. 10.
| Month | Avg. Low | Avg. High | Avg. Precip |
|---|---|---|---|
| January | 16.9 °F | 32.9 °F | 3.87 in. |
| February | 17.9 °F | 36.0 °F | 2.97 in. |
| March | 24.7 °F | 44.8 °F | 3.98 in. |
| April | 35.3 °F | 58.4 °F | 4.12 in. |
| May | 45.9 °F | 68.9 °F | 4.39 in. |
| June | 54.3 °F | 76.3 °F | 4.48 in. |
| July | 58.5 °F | 80.3 °F | 4.43 in. |
| August | 57.0 °F | 78.9 °F | 4.26 in. |
| September | 50.2 °F | 72.2 °F | 4.21 in. |
| October | 39.4 °F | 60.4 °F | 3.44 in. |
| November | 29.7 °F | 47.9 °F | 3.8 in. |
| December | 22.6 °F | 37.1 °F | 3.85 in. |
| Annual | 37.7 °F | 57.8 °F | 47.8 in. |
| Average First Frost Date | Oct. 1 - Oct. 10 |
| 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 5b : -15°F to -10°F |
| Current Drought Conditions | Normal |
| Köppen Climate Classification | Dfb - Humid Continental Mild Summer, Wet All Year |