Marklesburg, Pennsylvania has a Humid Continental Mild Summer, Wet All Year climate (Köppen classification: Dfb). Average annual temperatures range from 4.7 °C (low) to 16.3 °C (high). Annual precipitation averages 1051.1 Millimeters. Marklesburg is located in USDA Plant Hardiness Zone 7a. 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 | -6.7 °C | 2.6 °C | 72.14 mm |
| February | -6.1 °C | 4.3 °C | 60.2 mm |
| March | -2.4 °C | 9.1 °C | 83.57 mm |
| April | 3.3 °C | 16.4 °C | 91.44 mm |
| May | 9.1 °C | 22 °C | 104.39 mm |
| June | 14 °C | 26.3 °C | 102.11 mm |
| July | 16.4 °C | 28.9 °C | 92.2 mm |
| August | 15.6 °C | 28.1 °C | 95.5 mm |
| September | 11.7 °C | 24.2 °C | 103.89 mm |
| October | 5.3 °C | 17.7 °C | 88.65 mm |
| November | 0.1 °C | 10.9 °C | 76.2 mm |
| December | -3.8 °C | 4.8 °C | 80.77 mm |
| Annual | 4.7 °C | 16.3 °C | 1051.06 mm |
| Average First Frost Date | Oct. 21 - Oct. 31 |
| Average Last Frost Date | Apr. 11 - Apr. 20 |
| Average Days With Frost | 100-125 Days |
| Plant Hardiness Zone | Zone 7a : -17.8°C to -15°C |
| Plant Hardiness Zone - 2012 | Zone 6b : -20.6°C to -17.8°C |
| Current Drought Conditions | Normal |
| Köppen Climate Classification | Dfb - Humid Continental Mild Summer, Wet All Year |