Oak Grove, Minnesota has a Humid Continental Mild Summer, Wet All Year climate (Köppen classification: Dfb). Average annual temperatures range from 1.5 °C (low) to 12.5 °C (high). Annual precipitation averages 862.6 Millimeters. Oak Grove is located in USDA Plant Hardiness Zone 4b. The growing season typically runs from the last frost around Apr. 21 - Apr. 30 through the first frost around Oct. 1 - Oct. 10.
| Month | Avg. Low | Avg. High | Avg. Precip |
|---|---|---|---|
| January | -14.9 °C | -5.1 °C | 21.59 mm |
| February | -13.1 °C | -2.2 °C | 22.35 mm |
| March | -6.3 °C | 4.9 °C | 41.15 mm |
| April | 0.9 °C | 13.1 °C | 76.2 mm |
| May | 7.9 °C | 20.3 °C | 113.54 mm |
| June | 13.6 °C | 25.2 °C | 119.38 mm |
| July | 16.3 °C | 27.9 °C | 118.87 mm |
| August | 14.8 °C | 26.5 °C | 113.03 mm |
| September | 10.2 °C | 22.3 °C | 91.44 mm |
| October | 3.2 °C | 14.3 °C | 71.37 mm |
| November | -3.8 °C | 5.4 °C | 43.69 mm |
| December | -10.9 °C | -2.2 °C | 29.97 mm |
| Annual | 1.5 °C | 12.5 °C | 862.58 mm |
| Average First Frost Date | Oct. 1 - Oct. 10 |
| Average Last Frost Date | Apr. 21 - Apr. 30 |
| Average Days With Frost | 150-180 Days |
| Plant Hardiness Zone | Zone 4b : -31.7°C to -28.9°C |
| Plant Hardiness Zone - 2012 | Zone 4a : -34.4°C to -31.7°C |
| Current Drought Conditions | Normal |
| Köppen Climate Classification | Dfb - Humid Continental Mild Summer, Wet All Year |