Hamer, Idaho has a Humid Continental Mild Summer, Wet All Year climate (Köppen classification: Dfb). Average annual temperatures range from 28.1 °F (low) to 56.8 °F (high). Annual precipitation averages 8.5 Inches. Hamer is located in USDA Plant Hardiness Zone 4b. The growing season typically runs from the last frost around Jun. 1 - Jun. 10 through the first frost around Sep.1 - Sep. 10.
| Month | Avg. Low | Avg. High | Avg. Precip |
|---|---|---|---|
| January | 7.3 °F | 27.5 °F | 0.61 in. |
| February | 11.1 °F | 32.4 °F | 0.39 in. |
| March | 21.2 °F | 45.6 °F | 0.52 in. |
| April | 28.5 °F | 57.6 °F | 0.8 in. |
| May | 36.8 °F | 66.8 °F | 1.49 in. |
| June | 43.0 °F | 75.5 °F | 1.04 in. |
| July | 48.2 °F | 85.6 °F | 0.44 in. |
| August | 46.5 °F | 85.0 °F | 0.54 in. |
| September | 38.4 °F | 74.7 °F | 0.67 in. |
| October | 28.4 °F | 59.2 °F | 0.82 in. |
| November | 18.7 °F | 42.5 °F | 0.52 in. |
| December | 9.5 °F | 29.1 °F | 0.69 in. |
| Annual | 28.1 °F | 56.8 °F | 8.53 in. |
| Average First Frost Date | Sep.1 - Sep. 10 |
| Average Last Frost Date | Jun. 1 - Jun. 10 |
| Average Days With Frost | Over 180 Days |
| Plant Hardiness Zone | Zone 4b : -25°F to -20°F |
| Plant Hardiness Zone - 2012 | Zone 4b : -25°F to -20°F |
| Current Drought Conditions | Extreme Drought |
| Köppen Climate Classification | Dfb - Humid Continental Mild Summer, Wet All Year |