Bryn Athyn, Pennsylvania has a Humid Continental Hot Summers With Year Around Precipitation climate (Köppen classification: Dfa). Average annual temperatures range from 45.7 °F (low) to 64.1 °F (high). Annual precipitation averages 48.7 Inches. Bryn Athyn is located in USDA Plant Hardiness Zone 7b. The growing season typically runs from the last frost around Apr. 11 - Apr. 20 through the first frost around Oct. 21 - Oct. 31.
| Month | Avg. Low | Avg. High | Avg. Precip |
|---|---|---|---|
| January | 24.7 °F | 40.5 °F | 3.54 in. |
| February | 26.1 °F | 43.3 °F | 2.65 in. |
| March | 33.0 °F | 51.2 °F | 4.27 in. |
| April | 43.0 °F | 63.2 °F | 3.77 in. |
| May | 52.8 °F | 72.8 °F | 4.15 in. |
| June | 62.3 °F | 81.9 °F | 4.44 in. |
| July | 67.8 °F | 86.4 °F | 4.8 in. |
| August | 66.1 °F | 84.7 °F | 5.13 in. |
| September | 58.9 °F | 78.2 °F | 4.34 in. |
| October | 47.2 °F | 66.3 °F | 3.95 in. |
| November | 37.1 °F | 55.2 °F | 3.3 in. |
| December | 29.8 °F | 45.2 °F | 4.33 in. |
| Annual | 45.7 °F | 64.1 °F | 48.67 in. |
| Average First Frost Date | Oct. 21 - Oct. 31 |
| Average Last Frost Date | Apr. 11 - Apr. 20 |
| Average Days With Frost | 75-100 Days |
| Plant Hardiness Zone | Zone 7b : 5°F to 10°F |
| Plant Hardiness Zone - 2012 | Zone 7a : 0°F to 5°F |
| Current Drought Conditions | Moderate Drought |
| Köppen Climate Classification | Dfa - Humid Continental Hot Summers With Year Around Precipitation |