Azusa, California has a Hot-Summer Mediterranean Climate climate (Köppen classification: Csa). Average annual temperatures range from 12 °C (low) to 25.8 °C (high). Annual precipitation averages 490 Millimeters. Azusa is located in USDA Plant Hardiness Zone 10a.
| Month | Avg. Low | Avg. High | Avg. Precip |
|---|---|---|---|
| January | 7.8 °C | 20.5 °C | 114.3 mm |
| February | 8.1 °C | 20.7 °C | 123.44 mm |
| March | 9.2 °C | 22.1 °C | 81.79 mm |
| April | 10.4 °C | 23.7 °C | 25.65 mm |
| May | 12.8 °C | 25.3 °C | 14.22 mm |
| June | 14.7 °C | 28.4 °C | 5.08 mm |
| July | 16.8 °C | 32.1 °C | 2.03 mm |
| August | 17.2 °C | 33.2 °C | 0.25 mm |
| September | 16.3 °C | 31.7 °C | 4.83 mm |
| October | 13.7 °C | 27.9 °C | 18.8 mm |
| November | 10.1 °C | 23.9 °C | 24.89 mm |
| December | 7.3 °C | 20 °C | 74.68 mm |
| Annual | 12 °C | 25.8 °C | 489.96 mm |
| Average First Frost Date | Jan. 21 - Jan. 31 |
| Average Last Frost Date | |
| Average Days With Frost | Frost Rare |
| Plant Hardiness Zone | Zone 10a : -1.1°C to 1.7°C |
| Plant Hardiness Zone - 2012 | Zone 10a : -1.1°C to 1.7°C |
| Current Drought Conditions | Normal |
| Köppen Climate Classification | Csa - Hot-Summer Mediterranean Climate |