Lewisville, Idaho has a Cold Semi-Arid Climate climate (Köppen classification: BSk). Average annual temperatures range from 30.1 °F (low) to 56.7 °F (high). Annual precipitation averages 10.2 Inches. Lewisville is located in USDA Plant Hardiness Zone 5a. The growing season typically runs from the last frost around May 21 - May 31 through the first frost around Sep.11 - Sep. 20.
| Month | Avg. Low | Avg. High | Avg. Precip |
|---|---|---|---|
| January | 10.4 °F | 28.4 °F | 0.78 in. |
| February | 14.0 °F | 33.2 °F | 0.53 in. |
| March | 23.6 °F | 46.2 °F | 0.78 in. |
| April | 29.9 °F | 56.9 °F | 1.02 in. |
| May | 37.8 °F | 65.9 °F | 1.64 in. |
| June | 44.2 °F | 74.5 °F | 1.13 in. |
| July | 49.6 °F | 84.7 °F | 0.52 in. |
| August | 47.7 °F | 84.3 °F | 0.61 in. |
| September | 40.0 °F | 74.0 °F | 0.87 in. |
| October | 30.3 °F | 59.3 °F | 0.93 in. |
| November | 21.0 °F | 42.8 °F | 0.62 in. |
| December | 12.2 °F | 29.9 °F | 0.81 in. |
| Annual | 30.1 °F | 56.7 °F | 10.24 in. |
| Average First Frost Date | Sep.11 - Sep. 20 |
| Average Last Frost Date | May 21 - May 31 |
| Average Days With Frost | Over 180 Days |
| Plant Hardiness Zone | Zone 5a : -20°F to -15°F |
| Plant Hardiness Zone - 2012 | Zone 5a : -20°F to -15°F |
| Current Drought Conditions | Extreme Drought |
| Köppen Climate Classification | BSk - Cold Semi-Arid Climate |