Millersburg, Pennsylvania has a Humid Continental Hot Summers With Year Around Precipitation climate (Köppen classification: Dfa). Average annual temperatures range from 41.7 °F (low) to 62 °F (high). Annual precipitation averages 46.1 Inches. Millersburg is located in USDA Plant Hardiness Zone 7a. The growing season typically runs from the last frost around Apr. 21 - Apr. 30 through the first frost around Oct. 21 - Oct. 31.
| Month | Avg. Low | Avg. High | Avg. Precip |
|---|---|---|---|
| January | 20.6 °F | 36.9 °F | 3.18 in. |
| February | 21.8 °F | 40.0 °F | 2.58 in. |
| March | 29.3 °F | 49.1 °F | 3.7 in. |
| April | 39.6 °F | 62.2 °F | 3.85 in. |
| May | 49.7 °F | 72.0 °F | 4.16 in. |
| June | 58.9 °F | 80.5 °F | 4.2 in. |
| July | 63.0 °F | 85.0 °F | 4.42 in. |
| August | 61.4 °F | 83.2 °F | 4.31 in. |
| September | 54.2 °F | 76.5 °F | 4.82 in. |
| October | 42.9 °F | 64.3 °F | 4.14 in. |
| November | 33.3 °F | 52.6 °F | 3.2 in. |
| December | 26.0 °F | 41.5 °F | 3.55 in. |
| Annual | 41.7 °F | 62 °F | 46.11 in. |
| Average First Frost Date | Oct. 21 - Oct. 31 |
| Average Last Frost Date | Apr. 21 - Apr. 30 |
| Average Days With Frost | 100-125 Days |
| Plant Hardiness Zone | Zone 7a : 0°F to 5°F |
| Plant Hardiness Zone - 2012 | Zone 6b : -5°F to 0°F |
| Current Drought Conditions | Abnormally Dry |
| Köppen Climate Classification | Dfa - Humid Continental Hot Summers With Year Around Precipitation |