Millinocket, Maine has a Humid Continental Mild Summer, Wet All Year climate (Köppen classification: Dfb). Average annual temperatures range from -0.2 °C (low) to 11.6 °C (high). Annual precipitation averages 1146.6 Millimeters. Millinocket 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 Sep. 21 - Sep. 30.
| Month | Avg. Low | Avg. High | Avg. Precip |
|---|---|---|---|
| January | -15.6 °C | -4.1 °C | 84.07 mm |
| February | -14.9 °C | -2.2 °C | 67.82 mm |
| March | -8.7 °C | 3.1 °C | 87.12 mm |
| April | -1.5 °C | 10.1 °C | 94.23 mm |
| May | 4.8 °C | 17.8 °C | 93.22 mm |
| June | 10.3 °C | 22.8 °C | 105.92 mm |
| July | 13.8 °C | 25.9 °C | 93.73 mm |
| August | 12.4 °C | 25.3 °C | 94.74 mm |
| September | 8.1 °C | 21.1 °C | 88.9 mm |
| October | 2 °C | 13.2 °C | 126.24 mm |
| November | -3.3 °C | 6.1 °C | 104.14 mm |
| December | -10.1 °C | -0.4 °C | 106.43 mm |
| Annual | -0.2 °C | 11.6 °C | 1146.56 mm |
| Average First Frost Date | Sep. 21 - Sep. 30 |
| Average Last Frost Date | May 11 - May 20 |
| Average Days With Frost | 150-180 Days |
| Plant Hardiness Zone | Zone 5a : -28.9°C to -26.1°C |
| Plant Hardiness Zone - 2012 | Zone 4b : -31.7°C to -28.9°C |
| Current Drought Conditions | Normal |
| Köppen Climate Classification | Dfb - Humid Continental Mild Summer, Wet All Year |