Sept-Îles, Quebec climate data is summarized below. Average annual temperatures range from -1.5 °C (low) to 6.2 °C (high). Annual precipitation averages 797 Millimeters. Sept-Îles 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. 21 - Sep. 30.
| Month | Avg. Low | Avg. High | Avg. Precip |
|---|---|---|---|
| January | -17.11 °C | -8.04 °C | 0 mm |
| February | -16.05 °C | -6.24 °C | 0 mm |
| March | -12.73 °C | -2.34 °C | 0 mm |
| April | -3.69 °C | 3.77 °C | 61 mm |
| May | 2.78 °C | 10.27 °C | 104 mm |
| June | 9 °C | 16 °C | 80 mm |
| July | 12.43 °C | 19.23 °C | 106 mm |
| August | 12.7 °C | 19.37 °C | 92 mm |
| September | 7.54 °C | 14.7 °C | 113 mm |
| October | 2.54 °C | 9.04 °C | 127 mm |
| November | -3.53 °C | 2.54 °C | 89 mm |
| December | -12.08 °C | -4.59 °C | 25 mm |
| Annual | -1.5 °C | 6.2 °C | 797 mm |
| Average First Frost Date | Sep. 21 - Sep. 30 |
| 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 | Normal |