Almonte, Ontario climate data is summarized below. Average annual temperatures range from 1.7 °C (low) to 11.8 °C (high). Annual precipitation averages 650 Millimeters. Almonte is located in USDA Plant Hardiness Zone 5a. The growing season typically runs from the last frost around May 1 - May 10 through the first frost around Sep. 21 - Sep. 30.
| Month | Avg. Low | Avg. High | Avg. Precip |
|---|---|---|---|
| January | -13.11 °C | -4.21 °C | 2 mm |
| February | -13.09 °C | -3.47 °C | 0 mm |
| March | -6.95 °C | 3.18 °C | 21 mm |
| April | 0.97 °C | 12.12 °C | 48 mm |
| May | 7.53 °C | 19.98 °C | 65 mm |
| June | 12.65 °C | 23.86 °C | 104 mm |
| July | 14.94 °C | 26.08 °C | 126 mm |
| August | 14.13 °C | 25.04 °C | 120 mm |
| September | 9.57 °C | 20.57 °C | 70 mm |
| October | 4.37 °C | 13.35 °C | 51 mm |
| November | -1.67 °C | 6.39 °C | 26 mm |
| December | -8.7 °C | -1.49 °C | 17 mm |
| Annual | 1.7 °C | 11.8 °C | 650 mm |
| Average First Frost Date | Sep. 21 - Sep. 30 |
| Average Last Frost Date | May 1 - May 10 |
| Average Days With Frost | 150-180 Days |
| Plant Hardiness Zone | Zone 5a : -28.9°C to -26.1°C |
| Current Drought Conditions | Normal |