Jay, Maine has a Humid Continental Mild Summer, Wet All Year climate (Köppen classification: Dfb). Average annual temperatures range from 0.9 °C (low) to 12.2 °C (high). Annual precipitation averages 1244.1 Millimeters. Jay 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 | -13.1 °C | -2.7 °C | 86.87 mm |
| February | -12.5 °C | -1.1 °C | 79.25 mm |
| March | -7 °C | 3.8 °C | 92.46 mm |
| April | -0.3 °C | 11.2 °C | 106.68 mm |
| May | 5.8 °C | 18.3 °C | 93.73 mm |
| June | 11.1 °C | 23 °C | 131.32 mm |
| July | 14.1 °C | 26 °C | 103.38 mm |
| August | 13 °C | 25.4 °C | 95 mm |
| September | 8.6 °C | 21.3 °C | 91.95 mm |
| October | 2.8 °C | 13.9 °C | 140.97 mm |
| November | -2.7 °C | 6.8 °C | 110.24 mm |
| December | -8.5 °C | 0.6 °C | 112.27 mm |
| Annual | 0.9 °C | 12.2 °C | 1244.12 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 5a : -28.9°C to -26.1°C |
| Current Drought Conditions | Normal |
| Köppen Climate Classification | Dfb - Humid Continental Mild Summer, Wet All Year |