Glendale, Colorado has a Humid Continental Mild Summer, Wet All Year climate (Köppen classification: Dfb). Average annual temperatures range from 35.5 °F (low) to 59.7 °F (high). Annual precipitation averages 21.8 Inches. Glendale is located in USDA Plant Hardiness Zone 6a. 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 | 21.6 °F | 42.0 °F | 0.72 in. |
| February | 20.3 °F | 42.9 °F | 1.18 in. |
| March | 25.9 °F | 49.9 °F | 1.89 in. |
| April | 30.6 °F | 55.2 °F | 3.25 in. |
| May | 39.7 °F | 63.8 °F | 3.19 in. |
| June | 48.8 °F | 75.8 °F | 1.84 in. |
| July | 55.7 °F | 82.1 °F | 2.35 in. |
| August | 53.7 °F | 80.0 °F | 2.01 in. |
| September | 46.3 °F | 72.7 °F | 2.18 in. |
| October | 35.8 °F | 60.0 °F | 1.45 in. |
| November | 26.9 °F | 49.8 °F | 0.92 in. |
| December | 20.9 °F | 41.9 °F | 0.84 in. |
| Annual | 35.5 °F | 59.7 °F | 21.82 in. |
| 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 6a : -10°F to -5°F |
| Plant Hardiness Zone - 2012 | Zone 5b : -15°F to -10°F |
| Current Drought Conditions | Severe Drought |
| Köppen Climate Classification | Dfb - Humid Continental Mild Summer, Wet All Year |