Princeton, Idaho has a Humid Continental Climate - Dry Cool Summer climate (Köppen classification: Dsb). Average annual temperatures range from 36.3 °F (low) to 58.5 °F (high). Annual precipitation averages 23.8 Inches. Princeton is located in USDA Plant Hardiness Zone 6b. The growing season typically runs from the last frost around May 11 - May 20 through the first frost around Sep.11 - Sep. 20.
| Month | Avg. Low | Avg. High | Avg. Precip |
|---|---|---|---|
| January | 25.8 °F | 37.2 °F | 2.89 in. |
| February | 26.6 °F | 41.2 °F | 2.2 in. |
| March | 30.2 °F | 48.5 °F | 2.41 in. |
| April | 34.8 °F | 56.3 °F | 2.16 in. |
| May | 40.9 °F | 65.9 °F | 2.35 in. |
| June | 45.6 °F | 71.3 °F | 1.7 in. |
| July | 49.3 °F | 82.8 °F | 0.7 in. |
| August | 48.7 °F | 84.2 °F | 0.64 in. |
| September | 42.7 °F | 74.5 °F | 0.85 in. |
| October | 35.7 °F | 59.6 °F | 2.06 in. |
| November | 30.4 °F | 44.7 °F | 2.87 in. |
| December | 24.9 °F | 36.1 °F | 3.01 in. |
| Annual | 36.3 °F | 58.5 °F | 23.84 in. |
| Average First Frost Date | Sep.11 - Sep. 20 |
| Average Last Frost Date | May 11 - May 20 |
| Average Days With Frost | 125-150 Days |
| Plant Hardiness Zone | Zone 6b : -5°F to 0°F |
| Plant Hardiness Zone - 2012 | Zone 6a : -10°F to -5°F |
| Current Drought Conditions | Severe Drought |
| Köppen Climate Classification | Dsb - Humid Continental Climate - Dry Cool Summer |