Dunes City, Oregon has a Warm-Summer Mediterranean Climate climate (Köppen classification: Csb). Average annual temperatures range from 6.9 °C (low) to 15.2 °C (high). Annual precipitation averages 1836.2 Millimeters. Dunes City is located in USDA Plant Hardiness Zone 9a. The growing season typically runs from the last frost around Mar. 21 - Mar. 31 through the first frost around Nov. 11 - Nov. 20.
| Month | Avg. Low | Avg. High | Avg. Precip |
|---|---|---|---|
| January | 4.1 °C | 11.1 °C | 282.45 mm |
| February | 3.9 °C | 12.1 °C | 203.45 mm |
| March | 4.4 °C | 12.7 °C | 218.69 mm |
| April | 5.5 °C | 13.7 °C | 162.31 mm |
| May | 7.6 °C | 16.1 °C | 96.27 mm |
| June | 9.5 °C | 17.7 °C | 62.74 mm |
| July | 10.8 °C | 19.8 °C | 15.24 mm |
| August | 10.8 °C | 19.3 °C | 23.62 mm |
| September | 9.6 °C | 19.5 °C | 53.34 mm |
| October | 7.7 °C | 16.4 °C | 141.99 mm |
| November | 5.4 °C | 13.1 °C | 258.57 mm |
| December | 3.8 °C | 10.6 °C | 317.5 mm |
| Annual | 6.9 °C | 15.2 °C | 1836.17 mm |
| Average First Frost Date | Nov. 11 - Nov. 20 |
| Average Last Frost Date | Mar. 21 - Mar. 31 |
| 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 | Moderate Drought |
| Köppen Climate Classification | Csb - Warm-Summer Mediterranean Climate |