Brogan, Oregon has a Cold Semi-Arid Climate climate (Köppen classification: BSk). Average annual temperatures range from 2.8 °C (low) to 17.6 °C (high). Annual precipitation averages 301.2 Millimeters. Brogan is located in USDA Plant Hardiness Zone 6b. The growing season typically runs from the last frost around Apr. 11 - Apr. 20 through the first frost around Oct. 21 - Oct. 31.
| Month | Avg. Low | Avg. High | Avg. Precip |
|---|---|---|---|
| January | -6.2 °C | 2.6 °C | 40.13 mm |
| February | -4.2 °C | 6.8 °C | 28.19 mm |
| March | -0.9 °C | 12.4 °C | 24.13 mm |
| April | 1.7 °C | 16.8 °C | 25.4 mm |
| May | 6.3 °C | 22.2 °C | 36.58 mm |
| June | 10.1 °C | 26.9 °C | 22.86 mm |
| July | 14 °C | 33.4 °C | 5.84 mm |
| August | 12.7 °C | 32.7 °C | 7.11 mm |
| September | 7.7 °C | 26.9 °C | 10.92 mm |
| October | 1.8 °C | 18.3 °C | 21.08 mm |
| November | -2.9 °C | 9.1 °C | 30.73 mm |
| December | -6.1 °C | 2.9 °C | 48.26 mm |
| Annual | 2.8 °C | 17.6 °C | 301.23 mm |
| Average First Frost Date | Oct. 21 - Oct. 31 |
| Average Last Frost Date | Apr. 11 - Apr. 20 |
| Average Days With Frost | 100-125 Days |
| Plant Hardiness Zone | Zone 6b : -20.6°C to -17.8°C |
| Plant Hardiness Zone - 2012 | Zone 6b : -20.6°C to -17.8°C |
| Current Drought Conditions | Moderate Drought |
| Köppen Climate Classification | BSk - Cold Semi-Arid Climate |