| 2023 Hardiness Zone: | Zone 6a: -10°F to -5°F Zone 6b: -5°F to 0°F Zone 7b: 5°F to 10°F Zone 7a: 0°F to 5°F |
| 2012 Hardiness Zone: | Zone 6a: -10°F to -5°F Zone 6b: -5°F to 0°F Zone 7b: 5°F to 10°F Zone 7a: 0°F to 5°F Zone 5b: -15°F to -10°F |
| 1990 Hardiness Zone: | Zone 6b: -5F to 0F |
| Average First Frost Date: | Sep. 21 - Sep. 30 |
| Average Last Frost Date: | May 21 - May 31 |
| Koppen-Geiger Climate Zone: | BSk - Cold Semi-Arid Climate |
| Ecoregion: | 10e - Pleistocene Lake Basins |
| Heat Zone Days: | 31 - 45 days Over 86°F |
Annual Climate Data for ZIP Code 98903 - Yakima, WA | Jan | Feb | Mar | Apr | May | Jun | Jul | Aug | Sep | Oct | Nov | Dec | Annual |
|---|---|---|---|---|---|---|---|---|---|---|---|---|---|
| Avg Min Temp (°F) | 21 | 25 | 30 | 34 | 41 | 47 | 52 | 51 | 44 | 34 | 27 | 21 | 36 |
| Avg Max Temp (°F) | 37 | 45 | 55 | 63 | 72 | 79 | 87 | 86 | 77 | 64 | 47 | 37 | 62 |
| Avg Precip (In.) | 1.24 | .85 | .74 | .56 | .54 | .64 | .23 | .39 | .38 | .56 | 1.14 | 1.44 | 8.72 |