Roseburg, Oregon has a Warm-Summer Mediterranean Climate climate (Köppen classification: Csb). Average annual temperatures range from 6.3 °C (low) to 19.1 °C (high). Annual precipitation averages 873.8 Millimeters. Roseburg is located in USDA Plant Hardiness Zone 9a. The growing season typically runs from the last frost around Mar. 11 - Mar. 20 through the first frost around Nov. 11 - Nov. 20.
| Month | Avg. Low | Avg. High | Avg. Precip |
|---|---|---|---|
| January | 2 °C | 9.7 °C | 131.32 mm |
| February | 2.2 °C | 11.9 °C | 95 mm |
| March | 3.1 °C | 14.7 °C | 102.36 mm |
| April | 4.7 °C | 17.3 °C | 75.18 mm |
| May | 7.5 °C | 21.4 °C | 55.88 mm |
| June | 10.1 °C | 25.1 °C | 26.16 mm |
| July | 12.4 °C | 29.9 °C | 7.62 mm |
| August | 12.1 °C | 30.4 °C | 7.62 mm |
| September | 9.5 °C | 27.1 °C | 22.61 mm |
| October | 6.3 °C | 19.7 °C | 62.48 mm |
| November | 4.2 °C | 12.6 °C | 127.51 mm |
| December | 2 °C | 8.8 °C | 160.02 mm |
| Annual | 6.3 °C | 19.1 °C | 873.76 mm |
| Average First Frost Date | Nov. 11 - Nov. 20 |
| Average Last Frost Date | Mar. 11 - Mar. 20 |
| Average Days With Frost | 20-30 Days |
| Plant Hardiness Zone | Zone 9a : -6.7°C to -3.9°C |
| Plant Hardiness Zone - 2012 | Zone 8b : -9.4°C to -6.7°C |
| Current Drought Conditions | Severe Drought |
| Köppen Climate Classification | Csb - Warm-Summer Mediterranean Climate |