Gary, Minnesota has a Humid Continental Mild Summer, Wet All Year climate (Köppen classification: Dfb). Average annual temperatures range from -1.1 °C (low) to 10.1 °C (high). Annual precipitation averages 622.3 Millimeters. Gary 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 | -18.8 °C | -9.1 °C | 19.81 mm |
| February | -17.2 °C | -6.5 °C | 17.53 mm |
| March | -9 °C | 0.9 °C | 24.89 mm |
| April | -0.8 °C | 10.6 °C | 36.32 mm |
| May | 6 °C | 18.8 °C | 77.98 mm |
| June | 12.3 °C | 23.9 °C | 109.73 mm |
| July | 14.3 °C | 26.3 °C | 85.34 mm |
| August | 12.8 °C | 25.9 °C | 75.18 mm |
| September | 7.9 °C | 21 °C | 73.15 mm |
| October | 1.2 °C | 12.2 °C | 57.15 mm |
| November | -6.8 °C | 2.3 °C | 22.61 mm |
| December | -14.6 °C | -5.6 °C | 22.61 mm |
| Annual | -1.1 °C | 10.1 °C | 622.3 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 |