Prompton, Pennsylvania has a Humid Continental Mild Summer, Wet All Year climate (Köppen classification: Dfb). Average annual temperatures range from 36.8 °F (low) to 57.5 °F (high). Annual precipitation averages 47 Inches. Prompton is located in USDA Plant Hardiness Zone 6a. The growing season typically runs from the last frost around May 1 - May 10 through the first frost around Oct. 1 - Oct. 10.
| Month | Avg. Low | Avg. High | Avg. Precip |
|---|---|---|---|
| January | 14.2 °F | 32.1 °F | 3.51 in. |
| February | 15.1 °F | 34.9 °F | 2.76 in. |
| March | 23.1 °F | 43.5 °F | 3.43 in. |
| April | 33.7 °F | 57.0 °F | 3.92 in. |
| May | 45.2 °F | 68.5 °F | 4.04 in. |
| June | 54.6 °F | 76.3 °F | 4.92 in. |
| July | 59.0 °F | 80.7 °F | 4.35 in. |
| August | 57.6 °F | 79.0 °F | 3.99 in. |
| September | 50.2 °F | 72.3 °F | 4.53 in. |
| October | 38.5 °F | 60.3 °F | 4.5 in. |
| November | 29.1 °F | 48.3 °F | 3.12 in. |
| December | 21.1 °F | 37.0 °F | 3.96 in. |
| Annual | 36.8 °F | 57.5 °F | 47.03 in. |
| Average First Frost Date | Oct. 1 - Oct. 10 |
| Average Last Frost Date | May 1 - May 10 |
| Average Days With Frost | 150-180 Days |
| Plant Hardiness Zone | Zone 6a : -10°F to -5°F |
| Plant Hardiness Zone - 2012 | Zone 5b : -15°F to -10°F |
| Current Drought Conditions | Normal |
| Köppen Climate Classification | Dfb - Humid Continental Mild Summer, Wet All Year |