Grassy Plains, British Columbia climate data is summarized below. Average annual temperatures range from -2.9 °C (low) to 5.8 °C (high). Annual precipitation averages 355 Millimeters. Grassy Plains is located in USDA Plant Hardiness Zone 3b. The growing season typically runs from the last frost around May 21 - May 31 through the first frost around Sep.1 - Sep. 10.
| Month | Avg. Low | Avg. High | Avg. Precip |
|---|---|---|---|
| January | -11.66 °C | -4.54 °C | 0 mm |
| February | -11.29 °C | -2.83 °C | 0 mm |
| March | -9.55 °C | -0.2 °C | 0 mm |
| April | -5.25 °C | 3.55 °C | 33 mm |
| May | 0.79 °C | 11.23 °C | 45 mm |
| June | 4.36 °C | 14.16 °C | 67 mm |
| July | 7.17 °C | 17.68 °C | 59 mm |
| August | 6.58 °C | 17.68 °C | 45 mm |
| September | 3.08 °C | 12.87 °C | 45 mm |
| October | -0.86 °C | 5.64 °C | 56 mm |
| November | -6.41 °C | -1.08 °C | 5 mm |
| December | -11.4 °C | -5.21 °C | 0 mm |
| Annual | -2.9 °C | 5.8 °C | 355 mm |
| Average First Frost Date | Sep.1 - Sep. 10 |
| Average Last Frost Date | May 21 - May 31 |
| Average Days With Frost | Over 180 Days |
| Plant Hardiness Zone | Zone 3b : -37.2°C to -34.4°C |
| Current Drought Conditions | Abnormally Dry |