Barrett, Minnesota has a Humid Continental Mild Summer, Wet All Year climate (Köppen classification: Dfb). Average annual temperatures range from 32.6 °F (low) to 52.3 °F (high). Annual precipitation averages 26.3 Inches. Barrett is located in USDA Plant Hardiness Zone 4b. 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 | 1.2 °F | 19.1 °F | 0.72 in. |
| February | 4.6 °F | 23.5 °F | 0.72 in. |
| March | 18.3 °F | 36.6 °F | 1.2 in. |
| April | 32.2 °F | 53.1 °F | 2.15 in. |
| May | 45.4 °F | 67.2 °F | 3.16 in. |
| June | 56.2 °F | 76.5 °F | 4.41 in. |
| July | 60.4 °F | 80.5 °F | 3.72 in. |
| August | 57.6 °F | 78.9 °F | 3.17 in. |
| September | 48.8 °F | 71.5 °F | 2.71 in. |
| October | 35.7 °F | 56.0 °F | 2.5 in. |
| November | 22.0 °F | 39.1 °F | 0.97 in. |
| December | 8.8 °F | 25.1 °F | 0.88 in. |
| Annual | 32.6 °F | 52.3 °F | 26.31 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 4b : -25°F to -20°F |
| Plant Hardiness Zone - 2012 | Zone 4a : -30°F to -25°F |
| Current Drought Conditions | Normal |
| Köppen Climate Classification | Dfb - Humid Continental Mild Summer, Wet All Year |