Millerton, Pennsylvania has a Humid Continental Mild Summer, Wet All Year climate (Köppen classification: Dfb). Average annual temperatures range from 2.1 °C (low) to 14.5 °C (high). Annual precipitation averages 958.9 Millimeters. Millerton is located in USDA Plant Hardiness Zone 5b. The growing season typically runs from the last frost around May 11 - May 20 through the first frost around Oct. 1 - Oct. 10.
| Month | Avg. Low | Avg. High | Avg. Precip |
|---|---|---|---|
| January | -9.9 °C | 0.2 °C | 58.42 mm |
| February | -9.4 °C | 1.8 °C | 46.99 mm |
| March | -5.5 °C | 6.4 °C | 69.34 mm |
| April | 0.3 °C | 14.2 °C | 85.09 mm |
| May | 6.4 °C | 21 °C | 81.53 mm |
| June | 11.6 °C | 25.3 °C | 104.9 mm |
| July | 13.9 °C | 27.7 °C | 96.01 mm |
| August | 13.2 °C | 26.8 °C | 93.98 mm |
| September | 9.3 °C | 23 °C | 101.6 mm |
| October | 3.4 °C | 16 °C | 91.19 mm |
| November | -1.7 °C | 8.6 °C | 66.55 mm |
| December | -5.9 °C | 2.8 °C | 63.25 mm |
| Annual | 2.1 °C | 14.5 °C | 958.85 mm |
| Average First Frost Date | Oct. 1 - Oct. 10 |
| Average Last Frost Date | May 11 - May 20 |
| Average Days With Frost | 150-180 Days |
| Plant Hardiness Zone | Zone 5b : -26.1°C to -23.3°C |
| Plant Hardiness Zone - 2012 | Zone 5b : -26.1°C to -23.3°C |
| Current Drought Conditions | Normal |
| Köppen Climate Classification | Dfb - Humid Continental Mild Summer, Wet All Year |