Bloomington, California has a Cold Semi-Arid Climate climate (Köppen classification: BSk). Average annual temperatures range from 11.2 °C (low) to 26.4 °C (high). Annual precipitation averages 338.6 Millimeters. Bloomington is located in USDA Plant Hardiness Zone 10a. The growing season typically runs from the last frost around Feb. 1 - Feb. 10 through the first frost around Dec. 11 - Dec. 20.
| Month | Avg. Low | Avg. High | Avg. Precip |
|---|---|---|---|
| January | 6.2 °C | 19.6 °C | 73.15 mm |
| February | 6.7 °C | 19.7 °C | 88.39 mm |
| March | 8.1 °C | 21.7 °C | 56.13 mm |
| April | 9.6 °C | 24.2 °C | 18.8 mm |
| May | 12.1 °C | 26.7 °C | 7.62 mm |
| June | 14.4 °C | 30.6 °C | 1.78 mm |
| July | 17.2 °C | 34.4 °C | 1.52 mm |
| August | 17.6 °C | 35.2 °C | 1.27 mm |
| September | 16.2 °C | 33.3 °C | 3.56 mm |
| October | 12.6 °C | 28.3 °C | 15.24 mm |
| November | 8.5 °C | 23.4 °C | 20.07 mm |
| December | 5.7 °C | 19.2 °C | 51.05 mm |
| Annual | 11.2 °C | 26.4 °C | 338.58 mm |
| Average First Frost Date | Dec. 11 - Dec. 20 |
| Average Last Frost Date | Feb. 1 - Feb. 10 |
| Average Days With Frost | 10-20 Days |
| Plant Hardiness Zone | Zone 10a : -1.1°C to 1.7°C |
| Plant Hardiness Zone - 2012 | Zone 9b : -3.9°C to -1.1°C |
| Current Drought Conditions | Normal |
| Köppen Climate Classification | BSk - Cold Semi-Arid Climate |