| 2023 Hardiness Zone: | Zone 8b: 15°F to 20°F Zone 9a: 20°F to 25°F |
| 2012 Hardiness Zone: | Zone 8b: 15°F to 20°F |
| 1990 Hardiness Zone: | Zone 8b: 15F to 20F |
| Average First Frost Date: | Nov. 1 - Nov. 10 |
| Average Last Frost Date: | Apr. 11 - Apr. 20 |
| Koppen-Geiger Climate Zone: | Csb - Warm-Summer Mediterranean Climate |
| Ecoregion: | 3d - Valley Foothills |
| Heat Zone Days: | Rare Over 86°F |
Annual Climate Data for ZIP Code 97080 - Gresham, OR | Jan | Feb | Mar | Apr | May | Jun | Jul | Aug | Sep | Oct | Nov | Dec | Annual |
|---|---|---|---|---|---|---|---|---|---|---|---|---|---|
| Avg Min Temp (°F) | 34 | 36 | 38 | 41 | 46 | 50 | 54 | 54 | 50 | 44 | 39 | 35 | 44 |
| Avg Max Temp (°F) | 46 | 51 | 56 | 61 | 68 | 73 | 80 | 81 | 76 | 64 | 52 | 45 | 63 |
| Avg Precip (In.) | 8.07 | 6.41 | 5.78 | 4.49 | 3.63 | 2.53 | 1.02 | 1.28 | 2.5 | 4.5 | 8.21 | 8.43 | 56.86 |