Adamstown, Pennsylvania has a Humid Continental Hot Summers With Year Around Precipitation climate (Köppen classification: Dfa). Average annual temperatures range from 6.4 °C (low) to 16.9 °C (high). Annual precipitation averages 1228.9 Millimeters. Adamstown 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. 11 - Oct. 20.
| Month | Avg. Low | Avg. High | Avg. Precip |
|---|---|---|---|
| January | -5.3 °C | 3.6 °C | 81.79 mm |
| February | -4.8 °C | 4.9 °C | 68.83 mm |
| March | -0.7 °C | 9.8 °C | 101.09 mm |
| April | 5.1 °C | 16.7 °C | 97.28 mm |
| May | 10.4 °C | 22 °C | 100.84 mm |
| June | 15.7 °C | 26.8 °C | 116.08 mm |
| July | 18.4 °C | 29.2 °C | 120.9 mm |
| August | 17.6 °C | 28.3 °C | 112.01 mm |
| September | 13.6 °C | 24.7 °C | 127 mm |
| October | 7.3 °C | 18.1 °C | 118.62 mm |
| November | 1.9 °C | 11.9 °C | 86.87 mm |
| December | -2.4 °C | 6.2 °C | 97.54 mm |
| Annual | 6.4 °C | 16.9 °C | 1228.85 mm |
| Average First Frost Date | Oct. 11 - Oct. 20 |
| Average Last Frost Date | Apr. 21 - Apr. 30 |
| 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 | Severe Drought |
| Köppen Climate Classification | Dfa - Humid Continental Hot Summers With Year Around Precipitation |