New Ulm, Minnesota has a Humid Continental Hot Summers With Year Around Precipitation climate (Köppen classification: Dfa). Average annual temperatures range from 1.8 °C (low) to 12.7 °C (high). Annual precipitation averages 790.2 Millimeters. New Ulm is located in USDA Plant Hardiness Zone 5a. The growing season typically runs from the last frost around Apr. 21 - Apr. 30 through the first frost around Oct. 1 - Oct. 10.
| Month | Avg. Low | Avg. High | Avg. Precip |
|---|---|---|---|
| January | -14.7 °C | -5.1 °C | 19.56 mm |
| February | -12.4 °C | -2.3 °C | 21.34 mm |
| March | -5.5 °C | 4.5 °C | 42.93 mm |
| April | 1.6 °C | 13.4 °C | 72.64 mm |
| May | 8.4 °C | 20.3 °C | 106.17 mm |
| June | 14.4 °C | 25.7 °C | 129.29 mm |
| July | 16.6 °C | 27.6 °C | 93.47 mm |
| August | 15 °C | 26.3 °C | 97.28 mm |
| September | 10.3 °C | 22.8 °C | 81.79 mm |
| October | 3.3 °C | 15.2 °C | 63.25 mm |
| November | -4.1 °C | 5.8 °C | 35.56 mm |
| December | -10.8 °C | -2 °C | 26.92 mm |
| Annual | 1.8 °C | 12.7 °C | 790.2 mm |
| Average First Frost Date | Oct. 1 - Oct. 10 |
| Average Last Frost Date | Apr. 21 - Apr. 30 |
| 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 | Abnormally Dry |
| Köppen Climate Classification | Dfa - Humid Continental Hot Summers With Year Around Precipitation |