Quincy, California has a Warm-Summer Mediterranean Climate climate (Köppen classification: Csb). Average annual temperatures range from 2.1 °C (low) to 19.7 °C (high). Annual precipitation averages 1095.8 Millimeters. Quincy is located in USDA Plant Hardiness Zone 7b. The growing season typically runs from the last frost around May 11 - May 20 through the first frost around Sep. 21 - Sep. 30.
| Month | Avg. Low | Avg. High | Avg. Precip |
|---|---|---|---|
| January | -3.2 °C | 8.6 °C | 180.85 mm |
| February | -2.8 °C | 11.2 °C | 183.64 mm |
| March | -1.1 °C | 13.8 °C | 164.08 mm |
| April | 0.4 °C | 17.3 °C | 88.65 mm |
| May | 3.8 °C | 22.2 °C | 55.12 mm |
| June | 6.9 °C | 27.7 °C | 19.56 mm |
| July | 9.9 °C | 32.6 °C | 3.05 mm |
| August | 8.7 °C | 32.1 °C | 4.32 mm |
| September | 5.4 °C | 28.8 °C | 13.46 mm |
| October | 1.3 °C | 21.7 °C | 55.12 mm |
| November | -1.3 °C | 13.1 °C | 110.74 mm |
| December | -3.3 °C | 7.7 °C | 217.17 mm |
| Annual | 2.1 °C | 19.7 °C | 1095.76 mm |
| Average First Frost Date | Sep. 21 - Sep. 30 |
| Average Last Frost Date | May 11 - May 20 |
| Average Days With Frost | 125-150 Days |
| Plant Hardiness Zone | Zone 7b : -15°C to -12.2°C |
| Plant Hardiness Zone - 2012 | Zone 7b : -15°C to -12.2°C |
| Current Drought Conditions | Abnormally Dry |
| Köppen Climate Classification | Csb - Warm-Summer Mediterranean Climate |