Leechburg, Pennsylvania has a Humid Continental Hot Summers With Year Around Precipitation climate (Köppen classification: Dfa). Average annual temperatures range from 5.2 °C (low) to 16.8 °C (high). Annual precipitation averages 1102.9 Millimeters. Leechburg is located in USDA Plant Hardiness Zone 6b. The growing season typically runs from the last frost around May 1 - May 10 through the first frost around Oct. 11 - Oct. 20.
| Month | Avg. Low | Avg. High | Avg. Precip |
|---|---|---|---|
| January | -6.3 °C | 2.9 °C | 82.04 mm |
| February | -5.8 °C | 4.7 °C | 65.28 mm |
| March | -2 °C | 9.7 °C | 81.28 mm |
| April | 3.6 °C | 17.3 °C | 93.22 mm |
| May | 9.7 °C | 22.9 °C | 102.87 mm |
| June | 14.6 °C | 27.1 °C | 115.06 mm |
| July | 16.8 °C | 29.2 °C | 116.59 mm |
| August | 16.1 °C | 28.4 °C | 102.62 mm |
| September | 12.2 °C | 24.8 °C | 101.6 mm |
| October | 6.1 °C | 17.9 °C | 79.76 mm |
| November | 0.7 °C | 11.2 °C | 81.28 mm |
| December | -3.3 °C | 5.3 °C | 81.28 mm |
| Annual | 5.2 °C | 16.8 °C | 1102.88 mm |
| Average First Frost Date | Oct. 11 - Oct. 20 |
| Average Last Frost Date | May 1 - May 10 |
| Average Days With Frost | 125-150 Days |
| Plant Hardiness Zone | Zone 6b : -20.6°C to -17.8°C |
| Plant Hardiness Zone - 2012 | Zone 6a : -23.3°C to -20.6°C |
| Current Drought Conditions | Normal |
| Köppen Climate Classification | Dfa - Humid Continental Hot Summers With Year Around Precipitation |