Salem, Oregon has a Warm-Summer Mediterranean Climate climate (Köppen classification: Csb). Average annual temperatures range from 6.2 °C (low) to 17.5 °C (high). Annual precipitation averages 1073.7 Millimeters. Salem is located in USDA Plant Hardiness Zone 8b. The growing season typically runs from the last frost around Apr. 11 - Apr. 20 through the first frost around Nov. 1 - Nov. 10.
| Month | Avg. Low | Avg. High | Avg. Precip |
|---|---|---|---|
| January | 1.9 °C | 8.6 °C | 151.64 mm |
| February | 1.9 °C | 10.7 °C | 119.13 mm |
| March | 3.2 °C | 13.2 °C | 126.75 mm |
| April | 4.8 °C | 15.8 °C | 87.12 mm |
| May | 7.6 °C | 19.9 °C | 57.4 mm |
| June | 9.9 °C | 23 °C | 38.61 mm |
| July | 11.9 °C | 27.9 °C | 9.14 mm |
| August | 11.8 °C | 28.2 °C | 11.18 mm |
| September | 9.8 °C | 24.8 °C | 38.86 mm |
| October | 6.4 °C | 17.9 °C | 90.93 mm |
| November | 3.8 °C | 11.7 °C | 157.23 mm |
| December | 1.7 °C | 8.1 °C | 185.67 mm |
| Annual | 6.2 °C | 17.5 °C | 1073.66 mm |
| Average First Frost Date | Nov. 1 - Nov. 10 |
| Average Last Frost Date | Apr. 11 - Apr. 20 |
| Average Days With Frost | 40-50 Days |
| Plant Hardiness Zone | Zone 8b : -9.4°C to -6.7°C |
| Plant Hardiness Zone - 2012 | Zone 8b : -9.4°C to -6.7°C |
| Current Drought Conditions | Moderate Drought |
| Köppen Climate Classification | Csb - Warm-Summer Mediterranean Climate |