| 2023 Hardiness Zone: | Zone 8b: 15°F to 20°F Zone 9a: 20°F to 25°F Zone 8a: 10°F to 15°F |
| 2012 Hardiness Zone: | Zone 8b: 15°F to 20°F Zone 8a: 10°F to 15°F |
| 1990 Hardiness Zone: | Zone 8b: 15F to 20F |
| Average First Frost Date: | Nov. 1 - Nov. 10 |
| Average Last Frost Date: | Apr. 1 - Apr. 10 |
| Koppen-Geiger Climate Zone: | Csb - Warm-Summer Mediterranean Climate |
| Ecoregion: | 1d - Volcanics |
| Heat Zone Days: | Rare Over 86°F |
Annual Climate Data for ZIP Code 97231 - Portland, OR | Jan | Feb | Mar | Apr | May | Jun | Jul | Aug | Sep | Oct | Nov | Dec | Annual |
|---|---|---|---|---|---|---|---|---|---|---|---|---|---|
| Avg Min Temp (°F) | 34 | 36 | 38 | 41 | 46 | 51 | 54 | 54 | 51 | 44 | 39 | 35 | 44 |
| Avg Max Temp (°F) | 46 | 50 | 55 | 60 | 67 | 73 | 79 | 80 | 76 | 64 | 52 | 46 | 62 |
| Avg Precip (In.) | 7.52 | 6.11 | 5.2 | 3.49 | 2.59 | 1.72 | .71 | .97 | 1.88 | 3.93 | 8.07 | 8.63 | 50.82 |