Deer Park, California has a Warm-Summer Mediterranean Climate climate (Köppen classification: Csb). Average annual temperatures range from 8.8 °C (low) to 23.2 °C (high). Annual precipitation averages 930.2 Millimeters. Deer Park is located in USDA Plant Hardiness Zone 9b. The growing season typically runs from the last frost around Feb. 21 - Feb. 29 through the first frost around Dec. 1 - Dec. 10.
| Month | Avg. Low | Avg. High | Avg. Precip |
|---|---|---|---|
| January | 4.1 °C | 14.2 °C | 185.17 mm |
| February | 4.7 °C | 15.9 °C | 184.66 mm |
| March | 5.8 °C | 18.1 °C | 128.27 mm |
| April | 7.4 °C | 21.1 °C | 56.39 mm |
| May | 9.9 °C | 24.9 °C | 32.51 mm |
| June | 12.3 °C | 29.6 °C | 5.84 mm |
| July | 13.9 °C | 32.6 °C | 0 mm |
| August | 13.6 °C | 32.6 °C | 1.02 mm |
| September | 12.8 °C | 31 °C | 2.29 mm |
| October | 10.3 °C | 26.3 °C | 45.21 mm |
| November | 6.6 °C | 18.4 °C | 88.9 mm |
| December | 4.2 °C | 14.1 °C | 199.9 mm |
| Annual | 8.8 °C | 23.2 °C | 930.16 mm |
| Average First Frost Date | Dec. 1 - Dec. 10 |
| Average Last Frost Date | Feb. 21 - Feb. 29 |
| Average Days With Frost | 10-20 Days |
| Plant Hardiness Zone | Zone 9b : -3.9°C to -1.1°C |
| Plant Hardiness Zone - 2012 | Zone 9a : -6.7°C to -3.9°C |
| Current Drought Conditions | Normal |
| Köppen Climate Classification | Csb - Warm-Summer Mediterranean Climate |