Gem Lake, Minnesota has a Humid Continental Mild Summer, Wet All Year climate (Köppen classification: Dfb). Average annual temperatures range from 2.4 °C (low) to 12.6 °C (high). Annual precipitation averages 861.8 Millimeters. Gem Lake is located in USDA Plant Hardiness Zone 5a. The growing season typically runs from the last frost around Apr. 21 - Apr. 30 through the first frost around Oct. 11 - Oct. 20.
| Month | Avg. Low | Avg. High | Avg. Precip |
|---|---|---|---|
| January | -13.9 °C | -4.9 °C | 24.64 mm |
| February | -12.2 °C | -2.2 °C | 23.37 mm |
| March | -5.5 °C | 4.9 °C | 44.2 mm |
| April | 1.8 °C | 13.1 °C | 79.76 mm |
| May | 8.8 °C | 20.2 °C | 108.71 mm |
| June | 14.6 °C | 25.5 °C | 121.41 mm |
| July | 17.3 °C | 27.9 °C | 110.74 mm |
| August | 15.8 °C | 26.7 °C | 111.51 mm |
| September | 11.2 °C | 22.4 °C | 87.38 mm |
| October | 3.8 °C | 14.3 °C | 74.68 mm |
| November | -3.3 °C | 5.6 °C | 42.16 mm |
| December | -10.1 °C | -2 °C | 33.27 mm |
| Annual | 2.4 °C | 12.6 °C | 861.83 mm |
| Average First Frost Date | Oct. 11 - Oct. 20 |
| Average Last Frost Date | Apr. 21 - Apr. 30 |
| Average Days With Frost | 125-150 Days |
| Plant Hardiness Zone | Zone 5a : -28.9°C to -26.1°C |
| Plant Hardiness Zone - 2012 | Zone 4b : -31.7°C to -28.9°C |
| Current Drought Conditions | Normal |
| Köppen Climate Classification | Dfb - Humid Continental Mild Summer, Wet All Year |