Oronoco, Minnesota has a Humid Continental Mild Summer, Wet All Year climate (Köppen classification: Dfb). Average annual temperatures range from 35.1 °F (low) to 54.5 °F (high). Annual precipitation averages 35.3 Inches. Oronoco is located in USDA Plant Hardiness Zone 4b. 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 | 6.0 °F | 23.1 °F | 1.01 in. |
| February | 9.7 °F | 27.8 °F | 1.07 in. |
| March | 22.0 °F | 40.2 °F | 1.97 in. |
| April | 34.3 °F | 55.3 °F | 3.52 in. |
| May | 46.5 °F | 67.8 °F | 4.38 in. |
| June | 57.0 °F | 77.5 °F | 5.32 in. |
| July | 60.8 °F | 81.2 °F | 4.32 in. |
| August | 58.4 °F | 79.0 °F | 4.82 in. |
| September | 50.3 °F | 72.2 °F | 3.61 in. |
| October | 37.5 °F | 58.6 °F | 2.42 in. |
| November | 25.4 °F | 42.2 °F | 1.61 in. |
| December | 13.5 °F | 28.9 °F | 1.29 in. |
| Annual | 35.1 °F | 54.5 °F | 35.34 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 4b : -25°F to -20°F |
| Plant Hardiness Zone - 2012 | Zone 4b : -25°F to -20°F |
| Current Drought Conditions | Moderate Drought |
| Köppen Climate Classification | Dfb - Humid Continental Mild Summer, Wet All Year |