Saint-Hyacinthe, Quebec climate data is summarized below. Average annual temperatures range from 2.5 °C (low) to 12 °C (high). Annual precipitation averages 933 Millimeters. Saint-Hyacinthe is located in USDA Plant Hardiness Zone 5b. The growing season typically runs from the last frost around May 1 - May 10 through the first frost around Oct. 1 - Oct. 10.
| Month | Avg. Low | Avg. High | Avg. Precip |
|---|---|---|---|
| January | -12.8 °C | -4.31 °C | 22 mm |
| February | -12.41 °C | -3.63 °C | 22 mm |
| March | -6.36 °C | 3.17 °C | 48 mm |
| April | 1.63 °C | 12.07 °C | 98 mm |
| May | 8.43 °C | 19.81 °C | 103 mm |
| June | 13.63 °C | 24.05 °C | 107 mm |
| July | 16.2 °C | 26.62 °C | 119 mm |
| August | 15.35 °C | 25.72 °C | 98 mm |
| September | 10.5 °C | 21.32 °C | 80 mm |
| October | 4.88 °C | 13.78 °C | 113 mm |
| November | -0.91 °C | 6.69 °C | 74 mm |
| December | -8.19 °C | -1.35 °C | 49 mm |
| Annual | 2.5 °C | 12 °C | 933 mm |
| Average First Frost Date | Oct. 1 - Oct. 10 |
| Average Last Frost Date | May 1 - May 10 |
| Average Days With Frost | 150-180 Days |
| Plant Hardiness Zone | Zone 5b : -26.1°C to -23.3°C |
| Current Drought Conditions | Normal |