| 2023 Hardiness Zone: | Zone 6a: -10°F to -5°F Zone 6b: -5°F to 0°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 |
| 1990 Hardiness Zone: | Zone 6a: -10F to -5F |
| 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: | 12i - Magic Valley |
| Heat Zone Days: | 46 - 60 days Over 86°F |
Annual Climate Data for ZIP Code 83338 - Jerome, ID | Jan | Feb | Mar | Apr | May | Jun | Jul | Aug | Sep | Oct | Nov | Dec | Annual |
|---|---|---|---|---|---|---|---|---|---|---|---|---|---|
| Avg Min Temp (°F) | 19 | 22 | 28 | 33 | 41 | 48 | 54 | 53 | 44 | 35 | 26 | 19 | 35 |
| Avg Max Temp (°F) | 36 | 42 | 52 | 61 | 71 | 80 | 90 | 89 | 78 | 65 | 47 | 37 | 62 |
| Avg Precip (In.) | 1.35 | 1.03 | 1.25 | .86 | 1.16 | .74 | .23 | .28 | .51 | .76 | 1.25 | 1.19 | 10.61 |