Brewer, Maine has a Humid Continental Mild Summer, Wet All Year climate (Köppen classification: Dfb). Average annual temperatures range from 33.8 °F (low) to 54.6 °F (high). Annual precipitation averages 45 Inches. Brewer is located in USDA Plant Hardiness Zone 5a. 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 | 7.6 °F | 28.2 °F | 3.32 in. |
| February | 9.6 °F | 31.2 °F | 2.95 in. |
| March | 20.4 °F | 39.5 °F | 3.76 in. |
| April | 31.6 °F | 52.1 °F | 3.88 in. |
| May | 42.0 °F | 64.6 °F | 3.4 in. |
| June | 50.9 °F | 73.8 °F | 3.95 in. |
| July | 57.4 °F | 79.5 °F | 3.24 in. |
| August | 55.5 °F | 78.4 °F | 3.33 in. |
| September | 47.9 °F | 70.3 °F | 3.85 in. |
| October | 37.1 °F | 57.3 °F | 4.73 in. |
| November | 28.3 °F | 45.5 °F | 4.02 in. |
| December | 16.9 °F | 34.4 °F | 4.59 in. |
| Annual | 33.8 °F | 54.6 °F | 45.02 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 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 |