Strathroy, Ontario climate data is summarized below. Average annual temperatures range from 4 °C (low) to 14.1 °C (high). Annual precipitation averages 568 Millimeters. Strathroy is located in USDA Plant Hardiness Zone 6b. The growing season typically runs from the last frost around May 1 - May 10 through the first frost around Oct. 11 - Oct. 20.
| Month | Avg. Low | Avg. High | Avg. Precip |
|---|---|---|---|
| January | -8.23 °C | -0.94 °C | 11 mm |
| February | -9.75 °C | -1.15 °C | 0 mm |
| March | -3.71 °C | 6.18 °C | 28 mm |
| April | 2.36 °C | 13.93 °C | 44 mm |
| May | 8.44 °C | 20.91 °C | 71 mm |
| June | 13.52 °C | 25.45 °C | 85 mm |
| July | 16.02 °C | 27.73 °C | 94 mm |
| August | 15.38 °C | 26.99 °C | 88 mm |
| September | 11.19 °C | 22.8 °C | 61 mm |
| October | 6.09 °C | 15.76 °C | 42 mm |
| November | 0.34 °C | 8.68 °C | 25 mm |
| December | -4.03 °C | 2.16 °C | 19 mm |
| Annual | 4 °C | 14.1 °C | 568 mm |
| Average First Frost Date | Oct. 11 - Oct. 20 |
| Average Last Frost Date | May 1 - May 10 |
| Average Days With Frost | 125-150 Days |
| Plant Hardiness Zone | Zone 6b : -20.6°C to -17.8°C |
| Current Drought Conditions | Normal |