Stanley, Idaho has a Humid Continental Climate - Dry Cool Summer climate (Köppen classification: Dsb). Average annual temperatures range from 21 °F (low) to 53 °F (high). Annual precipitation averages 17 Inches. Stanley is located in USDA Plant Hardiness Zone 4a. The growing season typically runs from the last frost around Jun. 11 - Jun. 20 through the first frost around Year Round Frost.
| Month | Avg. Low | Avg. High | Avg. Precip |
|---|---|---|---|
| January | 3.7 °F | 29.0 °F | 1.88 in. |
| February | 5.5 °F | 34.8 °F | 1.76 in. |
| March | 13.5 °F | 43.0 °F | 1.62 in. |
| April | 21.3 °F | 49.2 °F | 1.61 in. |
| May | 28.8 °F | 59.3 °F | 1.5 in. |
| June | 34.2 °F | 68.1 °F | 1.18 in. |
| July | 38.2 °F | 79.8 °F | 0.38 in. |
| August | 36.1 °F | 79.3 °F | 0.33 in. |
| September | 29.7 °F | 69.9 °F | 0.73 in. |
| October | 23.1 °F | 55.9 °F | 1.4 in. |
| November | 13.9 °F | 39.3 °F | 1.83 in. |
| December | 4.2 °F | 27.9 °F | 2.82 in. |
| Annual | 21 °F | 53 °F | 17.04 in. |
| Average First Frost Date | Year Round Frost |
| Average Last Frost Date | Jun. 11 - Jun. 20 |
| Average Days With Frost | Over 180 Days |
| Plant Hardiness Zone | Zone 4a : -30°F to -25°F |
| Plant Hardiness Zone - 2012 | Zone 3b : -35°F to -30°F |
| Current Drought Conditions | Moderate Drought |
| Köppen Climate Classification | Dsb - Humid Continental Climate - Dry Cool Summer |