Flemington, Pennsylvania has a Humid Continental Hot Summers With Year Around Precipitation climate (Köppen classification: Dfa). Average annual temperatures range from 4.4 °C (low) to 16.3 °C (high). Annual precipitation averages 1045 Millimeters. Flemington is located in USDA Plant Hardiness Zone 6b. 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 | -7.3 °C | 1.8 °C | 70.87 mm |
| February | -6.8 °C | 3.7 °C | 54.86 mm |
| March | -2.8 °C | 8.9 °C | 77.22 mm |
| April | 2.9 °C | 16.7 °C | 90.68 mm |
| May | 8.7 °C | 22.8 °C | 97.54 mm |
| June | 13.8 °C | 27 °C | 95 mm |
| July | 16.3 °C | 29.5 °C | 107.95 mm |
| August | 15.4 °C | 28.3 °C | 104.65 mm |
| September | 11.3 °C | 24.2 °C | 107.44 mm |
| October | 5.1 °C | 17.7 °C | 89.41 mm |
| November | -0.3 °C | 10.4 °C | 74.42 mm |
| December | -4.1 °C | 4.2 °C | 74.93 mm |
| Annual | 4.4 °C | 16.3 °C | 1044.97 mm |
| 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 6b : -20.6°C to -17.8°C |
| Plant Hardiness Zone - 2012 | Zone 6b : -20.6°C to -17.8°C |
| Current Drought Conditions | Normal |
| Köppen Climate Classification | Dfa - Humid Continental Hot Summers With Year Around Precipitation |