Monroe, South Dakota has a Humid Continental Hot Summers With Year Around Precipitation climate (Köppen classification: Dfa). Average annual temperatures range from 1.7 °C (low) to 13.5 °C (high). Annual precipitation averages 684.3 Millimeters. Monroe is located in USDA Plant Hardiness Zone 5a. The growing season typically runs from the last frost around May 1 - May 10 through the first frost around Oct. 1 - Oct. 10.
| Month | Avg. Low | Avg. High | Avg. Precip |
|---|---|---|---|
| January | -14.2 °C | -3.7 °C | 13.72 mm |
| February | -11.8 °C | -0.8 °C | 19.3 mm |
| March | -5.6 °C | 5.9 °C | 33.78 mm |
| April | 1 °C | 13.8 °C | 72.64 mm |
| May | 8.1 °C | 20.6 °C | 96.77 mm |
| June | 14.4 °C | 26.2 °C | 107.44 mm |
| July | 16.6 °C | 28.8 °C | 77.98 mm |
| August | 15.2 °C | 27.3 °C | 85.34 mm |
| September | 10.1 °C | 23.4 °C | 71.12 mm |
| October | 2.4 °C | 15.6 °C | 60.45 mm |
| November | -5.2 °C | 6.4 °C | 25.91 mm |
| December | -11.2 °C | -1.2 °C | 19.81 mm |
| Annual | 1.7 °C | 13.5 °C | 684.26 mm |
| Average First Frost Date | Oct. 1 - Oct. 10 |
| Average Last Frost Date | May 1 - May 10 |
| Average Days With Frost | 150-180 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 | Moderate Drought |
| Köppen Climate Classification | Dfa - Humid Continental Hot Summers With Year Around Precipitation |