Fort Klamath, Oregon has a Continental Subarctic - Cold Dry Summer climate (Köppen classification: Dsc). Average annual temperatures range from -0.7 °C (low) to 15.5 °C (high). Annual precipitation averages 495.3 Millimeters. Fort Klamath is located in USDA Plant Hardiness Zone 6b. The growing season typically runs from the last frost around Jun. 11 - Jun. 20 through the first frost around Aug. 11 - Aug. 20.
| Month | Avg. Low | Avg. High | Avg. Precip |
|---|---|---|---|
| January | -6.5 °C | 4.5 °C | 85.6 mm |
| February | -5.4 °C | 6.6 °C | 54.61 mm |
| March | -3.3 °C | 9.7 °C | 52.07 mm |
| April | -1.6 °C | 12.9 °C | 35.31 mm |
| May | 1.4 °C | 18.2 °C | 33.78 mm |
| June | 3.9 °C | 22.8 °C | 14.22 mm |
| July | 6.9 °C | 28.6 °C | 7.62 mm |
| August | 5.9 °C | 28.4 °C | 7.62 mm |
| September | 2.4 °C | 24.8 °C | 10.92 mm |
| October | -1.2 °C | 17.2 °C | 28.45 mm |
| November | -3.8 °C | 8.6 °C | 65.02 mm |
| December | -6.6 °C | 4 °C | 100.08 mm |
| Annual | -0.7 °C | 15.5 °C | 495.3 mm |
| Average First Frost Date | Aug. 11 - Aug. 20 |
| Average Last Frost Date | Jun. 11 - Jun. 20 |
| Average Days With Frost | Over 180 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 | Severe Drought |
| Köppen Climate Classification | Dsc - Continental Subarctic - Cold Dry Summer |