San Joaquin, California has a Cold Desert Climate climate (Köppen classification: BWk). Average annual temperatures range from 9.1 °C (low) to 24.6 °C (high). Annual precipitation averages 219.2 Millimeters. San Joaquin is located in USDA Plant Hardiness Zone 9a. The growing season typically runs from the last frost around Feb. 21 - Feb. 29 through the first frost around Nov. 21 - Nov. 30.
| Month | Avg. Low | Avg. High | Avg. Precip |
|---|---|---|---|
| January | 3 °C | 13.1 °C | 42.67 mm |
| February | 4.3 °C | 16.5 °C | 39.62 mm |
| March | 5.8 °C | 20.1 °C | 37.08 mm |
| April | 7.7 °C | 23.4 °C | 21.08 mm |
| May | 11.1 °C | 28.3 °C | 9.65 mm |
| June | 13.8 °C | 32.4 °C | 2.29 mm |
| July | 16.8 °C | 35.2 °C | 0 mm |
| August | 16.2 °C | 34.9 °C | 0.25 mm |
| September | 13.9 °C | 32.4 °C | 3.05 mm |
| October | 9.7 °C | 26.7 °C | 11.43 mm |
| November | 4.8 °C | 18.9 °C | 16.26 mm |
| December | 2.1 °C | 13.3 °C | 35.81 mm |
| Annual | 9.1 °C | 24.6 °C | 219.19 mm |
| Average First Frost Date | Nov. 21 - Nov. 30 |
| Average Last Frost Date | Feb. 21 - Feb. 29 |
| Average Days With Frost | 20-30 Days |
| Plant Hardiness Zone | Zone 9a : -6.7°C to -3.9°C |
| Plant Hardiness Zone - 2012 | Zone 9a : -6.7°C to -3.9°C |
| Current Drought Conditions | Normal |
| Köppen Climate Classification | BWk - Cold Desert Climate |