Devon, Pennsylvania has a Humid Continental Hot Summers With Year Around Precipitation climate (Köppen classification: Dfa). Average annual temperatures range from 42.8 °F (low) to 62.5 °F (high). Annual precipitation averages 48 Inches. Devon is located in USDA Plant Hardiness Zone 7a. The growing season typically runs from the last frost around Apr. 21 - Apr. 30 through the first frost around Oct. 11 - Oct. 20.
| Month | Avg. Low | Avg. High | Avg. Precip |
|---|---|---|---|
| January | 21.2 °F | 38.5 °F | 3.46 in. |
| February | 22.4 °F | 41.2 °F | 2.9 in. |
| March | 29.9 °F | 49.7 °F | 4.16 in. |
| April | 40.6 °F | 61.9 °F | 3.74 in. |
| May | 50.1 °F | 71.5 °F | 3.96 in. |
| June | 59.7 °F | 80.5 °F | 4.43 in. |
| July | 64.6 °F | 84.9 °F | 4.6 in. |
| August | 63.2 °F | 83.3 °F | 4.54 in. |
| September | 55.5 °F | 76.9 °F | 4.6 in. |
| October | 44.7 °F | 64.5 °F | 4.05 in. |
| November | 34.3 °F | 53.5 °F | 3.22 in. |
| December | 26.8 °F | 43.4 °F | 4.31 in. |
| Annual | 42.8 °F | 62.5 °F | 47.97 in. |
| Average First Frost Date | Oct. 11 - Oct. 20 |
| Average Last Frost Date | Apr. 21 - Apr. 30 |
| Average Days With Frost | 100-125 Days |
| Plant Hardiness Zone | Zone 7a : 0°F to 5°F |
| Plant Hardiness Zone - 2012 | Zone 6b : -5°F to 0°F |
| Current Drought Conditions | Severe Drought |
| Köppen Climate Classification | Dfa - Humid Continental Hot Summers With Year Around Precipitation |