Saco, Maine has a Humid Continental Mild Summer, Wet All Year climate (Köppen classification: Dfb). Average annual temperatures range from 38.7 °F (low) to 57.6 °F (high). Annual precipitation averages 48.6 Inches. Saco 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 | 15.3 °F | 33.6 °F | 3.55 in. |
| February | 16.8 °F | 35.8 °F | 3.61 in. |
| March | 25.5 °F | 43.4 °F | 4.59 in. |
| April | 35.7 °F | 55.1 °F | 4.31 in. |
| May | 45.7 °F | 66.1 °F | 3.6 in. |
| June | 55.3 °F | 75.3 °F | 4.34 in. |
| July | 61.4 °F | 80.6 °F | 3.07 in. |
| August | 60.1 °F | 79.7 °F | 3.42 in. |
| September | 52.7 °F | 72.6 °F | 3.71 in. |
| October | 41.8 °F | 60.7 °F | 5.34 in. |
| November | 31.9 °F | 49.4 °F | 4.38 in. |
| December | 22.4 °F | 39.3 °F | 4.66 in. |
| Annual | 38.7 °F | 57.6 °F | 48.58 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 | Moderate Drought |
| Köppen Climate Classification | Dfb - Humid Continental Mild Summer, Wet All Year |