Bly, Oregon has a Humid Continental Climate - Dry Cool Summer climate (Köppen classification: Dsb). Average annual temperatures range from -1 °C (low) to 16.5 °C (high). Annual precipitation averages 350.5 Millimeters. Bly is located in USDA Plant Hardiness Zone 6a. 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 | -6.5 °C | 5.6 °C | 44.7 mm |
| February | -5.7 °C | 7.5 °C | 30.73 mm |
| March | -3.7 °C | 10.5 °C | 41.15 mm |
| April | -2.2 °C | 13.7 °C | 37.59 mm |
| May | 1.2 °C | 18.9 °C | 29.97 mm |
| June | 4.2 °C | 24.1 °C | 19.3 mm |
| July | 7.1 °C | 30 °C | 14.48 mm |
| August | 5.9 °C | 29.4 °C | 9.65 mm |
| September | 1.9 °C | 25.7 °C | 10.41 mm |
| October | -2.4 °C | 18.3 °C | 22.35 mm |
| November | -4.6 °C | 9.8 °C | 37.85 mm |
| December | -7.2 °C | 4.7 °C | 52.32 mm |
| Annual | -1 °C | 16.5 °C | 350.5 mm |
| Average First Frost Date | Sep.11 - Sep. 20 |
| Average Last Frost Date | May 21 - May 31 |
| Average Days With Frost | 150-180 Days |
| Plant Hardiness Zone | Zone 6a : -23.3°C to -20.6°C |
| Plant Hardiness Zone - 2012 | Zone 6a : -23.3°C to -20.6°C |
| Current Drought Conditions | Moderate Drought |
| Köppen Climate Classification | Dsb - Humid Continental Climate - Dry Cool Summer |