Excelsior, Minnesota has a Humid Continental Mild Summer, Wet All Year climate (Köppen classification: Dfb). Average annual temperatures range from 2.4 °C (low) to 12.5 °C (high). Annual precipitation averages 811.3 Millimeters. Excelsior 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 | -14.4 °C | -5.2 °C | 22.35 mm |
| February | -12.6 °C | -2.6 °C | 22.61 mm |
| March | -5.6 °C | 4.4 °C | 39.88 mm |
| April | 1.9 °C | 12.9 °C | 71.63 mm |
| May | 9.1 °C | 20.2 °C | 106.93 mm |
| June | 14.8 °C | 25.5 °C | 117.86 mm |
| July | 17.3 °C | 28 °C | 104.39 mm |
| August | 16 °C | 26.8 °C | 110.74 mm |
| September | 11.4 °C | 22.7 °C | 82.8 mm |
| October | 4.1 °C | 14.5 °C | 61.98 mm |
| November | -3.1 °C | 5.5 °C | 37.85 mm |
| December | -10.6 °C | -2.3 °C | 32.26 mm |
| Annual | 2.4 °C | 12.5 °C | 811.28 mm |
| Average First Frost Date | Oct. 1 - Oct. 10 |
| Average Last Frost Date | Apr. 21 - Apr. 30 |
| Average Days With Frost | 125-150 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 | Normal |
| Köppen Climate Classification | Dfb - Humid Continental Mild Summer, Wet All Year |