La Union, New Mexico has a Cold Desert Climate climate (Köppen classification: BWk). Average annual temperatures range from 10.2 °C (low) to 26.1 °C (high). Annual precipitation averages 216.7 Millimeters. La Union is located in USDA Plant Hardiness Zone 8b. The growing season typically runs from the last frost around Mar. 1 - Mar. 10 through the first frost around Nov. 11 - Nov. 20.
| Month | Avg. Low | Avg. High | Avg. Precip |
|---|---|---|---|
| January | -0.6 °C | 15.1 °C | 11.18 mm |
| February | 1.9 °C | 18.1 °C | 11.18 mm |
| March | 5.5 °C | 22.3 °C | 6.86 mm |
| April | 9.2 °C | 26.7 °C | 3.56 mm |
| May | 13.9 °C | 31.6 °C | 4.06 mm |
| June | 19.3 °C | 36.2 °C | 12.95 mm |
| July | 21.3 °C | 35.7 °C | 36.83 mm |
| August | 20.6 °C | 34.4 °C | 45.47 mm |
| September | 17.1 °C | 31.6 °C | 41.91 mm |
| October | 10.5 °C | 26.7 °C | 17.02 mm |
| November | 3.8 °C | 20.2 °C | 7.62 mm |
| December | -0.4 °C | 14.8 °C | 18.03 mm |
| Annual | 10.2 °C | 26.1 °C | 216.67 mm |
| Average First Frost Date | Nov. 11 - Nov. 20 |
| Average Last Frost Date | Mar. 1 - Mar. 10 |
| Average Days With Frost | 40-50 Days |
| Plant Hardiness Zone | Zone 8b : -9.4°C to -6.7°C |
| Plant Hardiness Zone - 2012 | Zone 8a : -12.2°C to -9.4°C |
| Current Drought Conditions | Normal |
| Köppen Climate Classification | BWk - Cold Desert Climate |