Orrington, Maine has a Humid Continental Mild Summer, Wet All Year climate (Köppen classification: Dfb). Average annual temperatures range from 34.1 °F (low) to 54.3 °F (high). Annual precipitation averages 48.1 Inches. Orrington is located in USDA Plant Hardiness Zone 5a. The growing season typically runs from the last frost around May 11 - May 20 through the first frost around Oct. 1 - Oct. 10.
| Month | Avg. Low | Avg. High | Avg. Precip |
|---|---|---|---|
| January | 7.5 °F | 27.6 °F | 3.88 in. |
| February | 9.1 °F | 30.8 °F | 3.32 in. |
| March | 19.9 °F | 39.3 °F | 4.26 in. |
| April | 32.1 °F | 52.1 °F | 4.33 in. |
| May | 42.7 °F | 64.5 °F | 3.73 in. |
| June | 52.0 °F | 73.5 °F | 4.01 in. |
| July | 58.0 °F | 79.2 °F | 3.28 in. |
| August | 56.3 °F | 78.3 °F | 3.35 in. |
| September | 48.4 °F | 70.5 °F | 3.83 in. |
| October | 37.8 °F | 57.3 °F | 4.93 in. |
| November | 28.6 °F | 45.0 °F | 4.3 in. |
| December | 17.0 °F | 33.8 °F | 4.87 in. |
| Annual | 34.1 °F | 54.3 °F | 48.09 in. |
| Average First Frost Date | Oct. 1 - Oct. 10 |
| Average Last Frost Date | May 11 - May 20 |
| Average Days With Frost | 150-180 Days |
| Plant Hardiness Zone | Zone 5a : -20°F to -15°F |
| Plant Hardiness Zone - 2012 | Zone 5a : -20°F to -15°F |
| Current Drought Conditions | Moderate Drought |
| Köppen Climate Classification | Dfb - Humid Continental Mild Summer, Wet All Year |