Twin Valley, Minnesota has a Humid Continental Mild Summer, Wet All Year climate (Köppen classification: Dfb). Average annual temperatures range from -0.8 °C (low) to 10.3 °C (high). Annual precipitation averages 617.2 Millimeters. 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 | -18.6 °C | -8.9 °C | 19.05 mm |
| February | -16.9 °C | -6.2 °C | 15.24 mm |
| March | -8.8 °C | 1.2 °C | 24.13 mm |
| April | -0.7 °C | 10.8 °C | 37.59 mm |
| May | 6.3 °C | 18.9 °C | 79.5 mm |
| June | 12.6 °C | 24.2 °C | 109.98 mm |
| July | 14.7 °C | 26.6 °C | 84.07 mm |
| August | 13.2 °C | 26 °C | 74.42 mm |
| September | 8.3 °C | 21.2 °C | 73.15 mm |
| October | 1.4 °C | 12.4 °C | 57.4 mm |
| November | -6.5 °C | 2.6 °C | 22.35 mm |
| December | -14.2 °C | -5.3 °C | 20.32 mm |
| Annual | -0.8 °C | 10.3 °C | 617.2 mm |
| 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 : -34.4°C to -31.7°C |
| Plant Hardiness Zone - 2012 | Zone 3b : -37.2°C to -34.4°C |
| Current Drought Conditions | Abnormally Dry |
| Köppen Climate Classification | Dfb - Humid Continental Mild Summer, Wet All Year |