Lansdowne, Pennsylvania has a Humid Subtropical Climate climate (Köppen classification: Cfa). Average annual temperatures range from 8.9 °C (low) to 18.1 °C (high). Annual precipitation averages 1188.7 Millimeters. Lansdowne is located in USDA Plant Hardiness Zone 7b. The growing season typically runs from the last frost around Apr. 1 - Apr. 10 through the first frost around Nov. 1 - Nov. 10.
| Month | Avg. Low | Avg. High | Avg. Precip |
|---|---|---|---|
| January | -2.7 °C | 5 °C | 88.39 mm |
| February | -2.1 °C | 6.5 °C | 71.37 mm |
| March | 1.7 °C | 10.9 °C | 109.22 mm |
| April | 7.3 °C | 17.8 °C | 91.19 mm |
| May | 12.7 °C | 22.8 °C | 96.77 mm |
| June | 18 °C | 28.2 °C | 108.2 mm |
| July | 21 °C | 30.6 °C | 114.55 mm |
| August | 20.2 °C | 29.6 °C | 119.63 mm |
| September | 16.4 °C | 26.1 °C | 107.44 mm |
| October | 9.9 °C | 19.3 °C | 97.03 mm |
| November | 4.3 °C | 13.1 °C | 77.72 mm |
| December | 0.2 °C | 7.7 °C | 107.19 mm |
| Annual | 8.9 °C | 18.1 °C | 1188.7 mm |
| Average First Frost Date | Nov. 1 - Nov. 10 |
| Average Last Frost Date | Apr. 1 - Apr. 10 |
| Average Days With Frost | 75-100 Days |
| Plant Hardiness Zone | Zone 7b : -15°C to -12.2°C |
| Plant Hardiness Zone - 2012 | Zone 7a : -17.8°C to -15°C |
| Current Drought Conditions | Abnormally Dry |
| Köppen Climate Classification | Cfa - Humid Subtropical Climate |