Phelan, California has a Hot-Summer Mediterranean Climate climate (Köppen classification: Csa). Average annual temperatures range from 44.4 °F (low) to 72.8 °F (high). Annual precipitation averages 13.8 Inches. Phelan is located in USDA Plant Hardiness Zone 8b. The growing season typically runs from the last frost around Mar. 1 - Mar. 10 through the first frost around Dec. 1 - Dec. 10.
| Month | Avg. Low | Avg. High | Avg. Precip |
|---|---|---|---|
| January | 32.3 °F | 56.5 °F | 2.53 in. |
| February | 33.0 °F | 58.3 °F | 3.93 in. |
| March | 36.7 °F | 64.0 °F | 1.59 in. |
| April | 40.1 °F | 68.3 °F | 0.64 in. |
| May | 46.8 °F | 76.8 °F | 0.19 in. |
| June | 53.7 °F | 86.6 °F | 0.15 in. |
| July | 60.7 °F | 92.1 °F | 0.25 in. |
| August | 59.3 °F | 91.7 °F | 0.12 in. |
| September | 55.6 °F | 85.2 °F | 0.2 in. |
| October | 46.1 °F | 74.1 °F | 0.6 in. |
| November | 37.1 °F | 64.4 °F | 0.87 in. |
| December | 31.9 °F | 55.4 °F | 2.73 in. |
| Annual | 44.4 °F | 72.8 °F | 13.8 in. |
| Average First Frost Date | Dec. 1 - Dec. 10 |
| Average Last Frost Date | Mar. 1 - Mar. 10 |
| Average Days With Frost | 20-30 Days |
| Plant Hardiness Zone | Zone 8b : 15°F to 20°F |
| Plant Hardiness Zone - 2012 | Zone 8b : 15°F to 20°F |
| Current Drought Conditions | Normal |
| Köppen Climate Classification | Csa - Hot-Summer Mediterranean Climate |