Twin Valley, Minnesota has a Humid Continental Mild Summer, Wet All Year climate (Köppen classification: Dfb). Average annual temperatures range from 30.6 °F (low) to 50.5 °F (high). Annual precipitation averages 24.3 Inches. Twin Valley is located in USDA Plant Hardiness Zone 4a. The growing season typically runs from the last frost around May 1 - May 10 through the first frost around Sep. 21 - Sep. 30.
| Month | Avg. Low | Avg. High | Avg. Precip |
|---|---|---|---|
| January | -1.4 °F | 15.9 °F | 0.75 in. |
| February | 1.6 °F | 20.9 °F | 0.6 in. |
| March | 16.1 °F | 34.2 °F | 0.95 in. |
| April | 30.8 °F | 51.5 °F | 1.48 in. |
| May | 43.3 °F | 66.1 °F | 3.13 in. |
| June | 54.6 °F | 75.5 °F | 4.33 in. |
| July | 58.4 °F | 79.8 °F | 3.31 in. |
| August | 55.7 °F | 78.8 °F | 2.93 in. |
| September | 47.0 °F | 70.2 °F | 2.88 in. |
| October | 34.6 °F | 54.4 °F | 2.26 in. |
| November | 20.3 °F | 36.7 °F | 0.88 in. |
| December | 6.4 °F | 22.5 °F | 0.8 in. |
| Annual | 30.6 °F | 50.5 °F | 24.3 in. |
| Average First Frost Date | Sep. 21 - Sep. 30 |
| Average Last Frost Date | May 1 - May 10 |
| Average Days With Frost | 150-180 Days |
| Plant Hardiness Zone | Zone 4a : -30°F to -25°F |
| Plant Hardiness Zone - 2012 | Zone 3b : -35°F to -30°F |
| Current Drought Conditions | Abnormally Dry |
| Köppen Climate Classification | Dfb - Humid Continental Mild Summer, Wet All Year |