| 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 9a: 20°F to 25°F Zone 8a: 10°F to 15°F |
| 1990 Hardiness Zone: | Zone 8b: 15F to 20F |
| Average First Frost Date: | Nov. 21 - Nov. 30 |
| Average Last Frost Date: | Mar. 1 - Mar. 10 |
| Koppen-Geiger Climate Zone: | Csb - Warm-Summer Mediterranean Climate |
| Ecoregion: | 3a - Portland/Vancouver Basin |
| Heat Zone Days: | Rare Over 86°F |
Annual Climate Data for ZIP Code 97210 - Portland, OR | Jan | Feb | Mar | Apr | May | Jun | Jul | Aug | Sep | Oct | Nov | Dec | Annual |
|---|---|---|---|---|---|---|---|---|---|---|---|---|---|
| Avg Min Temp (°F) | 35 | 37 | 40 | 42 | 48 | 52 | 56 | 56 | 53 | 46 | 40 | 36 | 45 |
| Avg Max Temp (°F) | 46 | 51 | 56 | 60 | 67 | 73 | 79 | 80 | 75 | 64 | 52 | 46 | 62 |
| Avg Precip (In.) | 6.38 | 5.01 | 4.72 | 2.98 | 2.32 | 1.63 | .5 | .77 | 1.71 | 3.76 | 6.17 | 7.39 | 43.32 |