Osborn, Missouri has a Humid Continental Hot Summers With Year Around Precipitation climate (Köppen classification: Dfa). Average annual temperatures range from 5.9 °C (low) to 17.3 °C (high). Annual precipitation averages 1009.4 Millimeters. Osborn is located in USDA Plant Hardiness Zone 6a. The growing season typically runs from the last frost around Apr. 11 - Apr. 20 through the first frost around Oct. 11 - Oct. 20.
| Month | Avg. Low | Avg. High | Avg. Precip |
|---|---|---|---|
| January | -8.3 °C | 1.9 °C | 26.42 mm |
| February | -6.3 °C | 4.9 °C | 36.32 mm |
| March | -0.3 °C | 11.5 °C | 63.75 mm |
| April | 4.7 °C | 17.7 °C | 97.28 mm |
| May | 11.3 °C | 23 °C | 144.27 mm |
| June | 16.9 °C | 28.1 °C | 134.62 mm |
| July | 19.4 °C | 30.7 °C | 119.63 mm |
| August | 18.3 °C | 29.8 °C | 111.51 mm |
| September | 13.1 °C | 25.8 °C | 102.36 mm |
| October | 6.5 °C | 18.9 °C | 81.03 mm |
| November | 0.2 °C | 11.3 °C | 50.8 mm |
| December | -5.3 °C | 4.3 °C | 41.4 mm |
| Annual | 5.9 °C | 17.3 °C | 1009.39 mm |
| Average First Frost Date | Oct. 11 - Oct. 20 |
| Average Last Frost Date | Apr. 11 - Apr. 20 |
| Average Days With Frost | 100-125 Days |
| Plant Hardiness Zone | Zone 6a : -23.3°C to -20.6°C |
| Plant Hardiness Zone - 2012 | Zone 5b : -26.1°C to -23.3°C |
| Current Drought Conditions | Normal |
| Köppen Climate Classification | Dfa - Humid Continental Hot Summers With Year Around Precipitation |