Richfield, Idaho has a Humid Continental Climate - Dry Cool Summer climate (Köppen classification: Dsb). Average annual temperatures range from 32.8 °F (low) to 59.5 °F (high). Annual precipitation averages 10 Inches. Richfield is located in USDA Plant Hardiness Zone 6a. The growing season typically runs from the last frost around May 21 - May 31 through the first frost around Sep. 21 - Sep. 30.
| Month | Avg. Low | Avg. High | Avg. Precip |
|---|---|---|---|
| January | 15.0 °F | 32.6 °F | 1.51 in. |
| February | 18.0 °F | 37.7 °F | 0.82 in. |
| March | 25.3 °F | 48.5 °F | 1.02 in. |
| April | 30.9 °F | 58.1 °F | 0.87 in. |
| May | 39.0 °F | 67.6 °F | 1.07 in. |
| June | 45.6 °F | 77.2 °F | 0.63 in. |
| July | 52.8 °F | 88.3 °F | 0.14 in. |
| August | 51.3 °F | 87.3 °F | 0.28 in. |
| September | 42.9 °F | 76.6 °F | 0.51 in. |
| October | 32.6 °F | 61.7 °F | 0.84 in. |
| November | 23.6 °F | 45.6 °F | 0.89 in. |
| December | 16.1 °F | 33.0 °F | 1.38 in. |
| Annual | 32.8 °F | 59.5 °F | 9.96 in. |
| Average First Frost Date | Sep. 21 - Sep. 30 |
| Average Last Frost Date | May 21 - May 31 |
| Average Days With Frost | 150-180 Days |
| Plant Hardiness Zone | Zone 6a : -10°F to -5°F |
| Plant Hardiness Zone - 2012 | Zone 5b : -15°F to -10°F |
| Current Drought Conditions | Severe Drought |
| Köppen Climate Classification | Dsb - Humid Continental Climate - Dry Cool Summer |