Oldtown, Idaho has a Humid Continental Climate - Dry Cool Summer climate (Köppen classification: Dsb). Average annual temperatures range from 34.4 °F (low) to 57.7 °F (high). Annual precipitation averages 26.6 Inches. Oldtown is located in USDA Plant Hardiness Zone 6a. 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 | 22.4 °F | 33.7 °F | 3.14 in. |
| February | 22.9 °F | 39.1 °F | 2.24 in. |
| March | 27.0 °F | 47.9 °F | 2.83 in. |
| April | 32.2 °F | 57.1 °F | 2.27 in. |
| May | 39.9 °F | 67.9 °F | 2.22 in. |
| June | 45.5 °F | 73.7 °F | 2.13 in. |
| July | 49.6 °F | 84.1 °F | 0.99 in. |
| August | 48.2 °F | 84.1 °F | 0.63 in. |
| September | 40.8 °F | 73.2 °F | 0.98 in. |
| October | 33.4 °F | 56.9 °F | 2.16 in. |
| November | 28.0 °F | 41.7 °F | 3.3 in. |
| December | 22.5 °F | 33.2 °F | 3.71 in. |
| Annual | 34.4 °F | 57.7 °F | 26.6 in. |
| Average First Frost Date | Sep.11 - Sep. 20 |
| Average Last Frost Date | May 11 - May 20 |
| Average Days With Frost | 150-180 Days |
| Plant Hardiness Zone | Zone 6a : -10°F to -5°F |
| Plant Hardiness Zone - 2012 | Zone 6a : -10°F to -5°F |
| Current Drought Conditions | Moderate Drought |
| Köppen Climate Classification | Dsb - Humid Continental Climate - Dry Cool Summer |