Marion, Utah has a Humid Continental Mild Summer, Wet All Year climate (Köppen classification: Dfb). Average annual temperatures range from -1.5 °C (low) to 15 °C (high). Annual precipitation averages 420.9 Millimeters. Marion is located in USDA Plant Hardiness Zone 5b. The growing season typically runs from the last frost around May 21 - May 31 through the first frost around Sep.1 - Sep. 10.
| Month | Avg. Low | Avg. High | Avg. Precip |
|---|---|---|---|
| January | -11 °C | 1.9 °C | 44.7 mm |
| February | -9.5 °C | 3.9 °C | 34.54 mm |
| March | -5.4 °C | 8.9 °C | 37.59 mm |
| April | -2.2 °C | 13.4 °C | 38.1 mm |
| May | 1.4 °C | 18.7 °C | 42.16 mm |
| June | 4.9 °C | 24.8 °C | 25.4 mm |
| July | 9 °C | 29.9 °C | 21.08 mm |
| August | 8.5 °C | 28.9 °C | 27.18 mm |
| September | 3.9 °C | 23.8 °C | 38.61 mm |
| October | -1.3 °C | 16.3 °C | 40.13 mm |
| November | -6.2 °C | 7.9 °C | 36.58 mm |
| December | -10.3 °C | 1.9 °C | 34.8 mm |
| Annual | -1.5 °C | 15 °C | 420.87 mm |
| Average First Frost Date | Sep.1 - Sep. 10 |
| Average Last Frost Date | May 21 - May 31 |
| Average Days With Frost | Over 180 Days |
| Plant Hardiness Zone | Zone 5b : -26.1°C to -23.3°C |
| Plant Hardiness Zone - 2012 | Zone 5b : -26.1°C to -23.3°C |
| Current Drought Conditions | Severe Drought |
| Köppen Climate Classification | Dfb - Humid Continental Mild Summer, Wet All Year |