Milwaukie, Oregon has a Warm-Summer Mediterranean Climate climate (Köppen classification: Csb). Average annual temperatures range from 7.6 °C (low) to 17.4 °C (high). Annual precipitation averages 1097.5 Millimeters. Milwaukie is located in USDA Plant Hardiness Zone 9a. The growing season typically runs from the last frost around Feb. 21 - Feb. 29 through the first frost around Nov. 21 - Nov. 30.
| Month | Avg. Low | Avg. High | Avg. Precip |
|---|---|---|---|
| January | 2.6 °C | 8.4 °C | 166.12 mm |
| February | 2.9 °C | 10.6 °C | 110.74 mm |
| March | 4.2 °C | 13.3 °C | 118.87 mm |
| April | 6.2 °C | 16.3 °C | 92.46 mm |
| May | 9.1 °C | 20.3 °C | 63.25 mm |
| June | 11.5 °C | 23.1 °C | 43.18 mm |
| July | 13.7 °C | 27.3 °C | 11.43 mm |
| August | 13.8 °C | 27.7 °C | 15.24 mm |
| September | 11.5 °C | 24.4 °C | 39.88 mm |
| October | 7.9 °C | 17.9 °C | 97.54 mm |
| November | 4.9 °C | 11.7 °C | 160.27 mm |
| December | 2.4 °C | 8.1 °C | 178.56 mm |
| Annual | 7.6 °C | 17.4 °C | 1097.54 mm |
| Average First Frost Date | Nov. 21 - Nov. 30 |
| Average Last Frost Date | Feb. 21 - Feb. 29 |
| 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 | Abnormally Dry |
| Köppen Climate Classification | Csb - Warm-Summer Mediterranean Climate |