Pittsburg, California has a Warm-Summer Mediterranean Climate climate (Köppen classification: Csb). Average annual temperatures range from 9.9 °C (low) to 22.3 °C (high). Annual precipitation averages 421.6 Millimeters. Pittsburg is located in USDA Plant Hardiness Zone 9b. The growing season typically runs from the last frost around Feb. 11 - Feb. 20 through the first frost around Dec. 11 - Dec. 20.
| Month | Avg. Low | Avg. High | Avg. Precip |
|---|---|---|---|
| January | 4.4 °C | 13.3 °C | 85.6 mm |
| February | 5.8 °C | 15.8 °C | 82.3 mm |
| March | 7.6 °C | 18.5 °C | 57.4 mm |
| April | 9.1 °C | 20.9 °C | 31.5 mm |
| May | 11.4 °C | 24.3 °C | 14.22 mm |
| June | 13.7 °C | 28.1 °C | 3.56 mm |
| July | 14.7 °C | 30.8 °C | 0 mm |
| August | 14.7 °C | 30.4 °C | 0.76 mm |
| September | 14 °C | 28.8 °C | 1.52 mm |
| October | 11.3 °C | 24.7 °C | 19.05 mm |
| November | 7.1 °C | 18.2 °C | 41.4 mm |
| December | 4.4 °C | 13.4 °C | 84.33 mm |
| Annual | 9.9 °C | 22.3 °C | 421.64 mm |
| Average First Frost Date | Dec. 11 - Dec. 20 |
| Average Last Frost Date | Feb. 11 - Feb. 20 |
| Average Days With Frost | 10-20 Days |
| Plant Hardiness Zone | Zone 9b : -3.9°C to -1.1°C |
| Plant Hardiness Zone - 2012 | Zone 9b : -3.9°C to -1.1°C |
| Current Drought Conditions | Normal |
| Köppen Climate Classification | Csb - Warm-Summer Mediterranean Climate |