Arnot, Pennsylvania has a Humid Continental Mild Summer, Wet All Year climate (Köppen classification: Dfb). Average annual temperatures range from 35.7 °F (low) to 56.5 °F (high). Annual precipitation averages 40.3 Inches. Arnot is located in USDA Plant Hardiness Zone 6a. The growing season typically runs from the last frost around May 21 - May 31 through the first frost around Sep. 21 - Sep. 30.
| Month | Avg. Low | Avg. High | Avg. Precip |
|---|---|---|---|
| January | 14.6 °F | 31.4 °F | 2.79 in. |
| February | 15.1 °F | 33.9 °F | 2.15 in. |
| March | 22.2 °F | 42.2 °F | 2.97 in. |
| April | 32.6 °F | 56.2 °F | 3.51 in. |
| May | 44.0 °F | 67.7 °F | 3.43 in. |
| June | 52.6 °F | 75.4 °F | 3.96 in. |
| July | 56.7 °F | 79.7 °F | 3.95 in. |
| August | 55.1 °F | 78.1 °F | 3.68 in. |
| September | 47.9 °F | 71.2 °F | 4.24 in. |
| October | 37.2 °F | 59.3 °F | 3.77 in. |
| November | 29.2 °F | 46.6 °F | 2.86 in. |
| December | 21.1 °F | 35.7 °F | 2.94 in. |
| Annual | 35.7 °F | 56.5 °F | 40.25 in. |
| Average First Frost Date | Sep. 21 - Sep. 30 |
| Average Last Frost Date | May 21 - May 31 |
| Average Days With Frost | 125-150 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 |