Richlandtown, Pennsylvania has a Humid Continental Hot Summers With Year Around Precipitation climate (Köppen classification: Dfa). Average annual temperatures range from 41.8 °F (low) to 62.3 °F (high). Annual precipitation averages 50.8 Inches. Richlandtown is located in USDA Plant Hardiness Zone 7a. 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 | 20.8 °F | 38.0 °F | 3.68 in. |
| February | 21.9 °F | 40.7 °F | 3.08 in. |
| March | 29.2 °F | 49.4 °F | 4.23 in. |
| April | 39.7 °F | 62.0 °F | 4.03 in. |
| May | 49.3 °F | 71.6 °F | 4.32 in. |
| June | 58.5 °F | 80.3 °F | 4.99 in. |
| July | 63.3 °F | 85.0 °F | 4.99 in. |
| August | 61.7 °F | 83.1 °F | 4.36 in. |
| September | 54.6 °F | 76.6 °F | 4.81 in. |
| October | 43.0 °F | 64.6 °F | 4.36 in. |
| November | 33.0 °F | 53.3 °F | 3.46 in. |
| December | 26.3 °F | 42.9 °F | 4.5 in. |
| Annual | 41.8 °F | 62.3 °F | 50.81 in. |
| 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 7a : 0°F to 5°F |
| Plant Hardiness Zone - 2012 | Zone 6b : -5°F to 0°F |
| Current Drought Conditions | Moderate Drought |
| Köppen Climate Classification | Dfa - Humid Continental Hot Summers With Year Around Precipitation |