Georgetown, California has a Hot-Summer Mediterranean Climate climate (Köppen classification: Csa). Average annual temperatures range from 9.5 °C (low) to 21.1 °C (high). Annual precipitation averages 1263.4 Millimeters. Georgetown is located in USDA Plant Hardiness Zone 9b. The growing season typically runs from the last frost around Apr. 1 - Apr. 10 through the first frost around Nov. 1 - Nov. 10.
| Month | Avg. Low | Avg. High | Avg. Precip |
|---|---|---|---|
| January | 3.8 °C | 11.5 °C | 216.66 mm |
| February | 3.8 °C | 12.4 °C | 208.53 mm |
| March | 4.4 °C | 14.9 °C | 199.39 mm |
| April | 6.3 °C | 17.8 °C | 113.79 mm |
| May | 9.9 °C | 22.6 °C | 60.71 mm |
| June | 14 °C | 28.3 °C | 20.57 mm |
| July | 18.1 °C | 33.1 °C | 0.51 mm |
| August | 18.1 °C | 32.9 °C | 2.29 mm |
| September | 15.3 °C | 29.7 °C | 9.91 mm |
| October | 10.9 °C | 23.2 °C | 62.99 mm |
| November | 5.9 °C | 15.2 °C | 124.46 mm |
| December | 3.4 °C | 11 °C | 243.59 mm |
| Annual | 9.5 °C | 21.1 °C | 1263.4 mm |
| Average First Frost Date | Nov. 1 - Nov. 10 |
| Average Last Frost Date | Apr. 1 - Apr. 10 |
| Average Days With Frost | 30-40 Days |
| Plant Hardiness Zone | Zone 9b : -3.9°C to -1.1°C |
| Plant Hardiness Zone - 2012 | Zone 9a : -6.7°C to -3.9°C |
| Current Drought Conditions | Abnormally Dry |
| Köppen Climate Classification | Csa - Hot-Summer Mediterranean Climate |