Ovando, Montana has a Humid Continental Mild Summer, Wet All Year climate (Köppen classification: Dfb). Average annual temperatures range from -3 °C (low) to 13.3 °C (high). Annual precipitation averages 425.5 Millimeters. Ovando is located in USDA Plant Hardiness Zone 4a. The growing season typically runs from the last frost around May 11 - May 20 through the first frost around Sep. 21 - Sep. 30.
| Month | Avg. Low | Avg. High | Avg. Precip |
|---|---|---|---|
| January | -11.8 °C | -0.3 °C | 34.8 mm |
| February | -10.8 °C | 2.4 °C | 27.18 mm |
| March | -7.1 °C | 7.4 °C | 24.64 mm |
| April | -2.9 °C | 12.6 °C | 26.42 mm |
| May | 0.7 °C | 18.2 °C | 50.29 mm |
| June | 4.3 °C | 22.3 °C | 58.42 mm |
| July | 6.2 °C | 28.7 °C | 24.13 mm |
| August | 5.3 °C | 28.6 °C | 26.92 mm |
| September | 1.7 °C | 22.4 °C | 38.61 mm |
| October | -3.1 °C | 13.3 °C | 35.56 mm |
| November | -7.4 °C | 4.5 °C | 38.61 mm |
| December | -11.6 °C | -0.7 °C | 39.88 mm |
| Annual | -3 °C | 13.3 °C | 425.46 mm |
| Average First Frost Date | Sep. 21 - Sep. 30 |
| Average Last Frost Date | May 11 - May 20 |
| Average Days With Frost | Over 180 Days |
| Plant Hardiness Zone | Zone 4a : -34.4°C to -31.7°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 |