Carleton Place, Ontario climate data is summarized below. Average annual temperatures range from 34.8 °F (low) to 53 °F (high). Annual precipitation averages 27.4 Inches. Carleton Place 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 | -25.1 °F | -20.2 °F | 101.6 in. |
| February | -25.2 °F | -19.8 °F | 25.4 in. |
| March | -21.8 °F | -16.1 °F | 609.6 in. |
| April | -17.3 °F | -11.2 °F | 1422.4 in. |
| May | -13.7 °F | -6.8 °F | 1930.4 in. |
| June | -10.8 °F | -4.7 °F | 2819.4 in. |
| July | -9.6 °F | -3.3 °F | 3175 in. |
| August | -10 °F | -3.9 °F | 2870.2 in. |
| September | -12.6 °F | -6.4 °F | 1955.8 in. |
| October | -15.5 °F | -10.4 °F | 1473.2 in. |
| November | -18.8 °F | -14.3 °F | 787.4 in. |
| December | -22.7 °F | -18.7 °F | 482.6 in. |
| Annual | 34.8 °F | 53 °F | 27.35 in. |
| 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 : -20°F to -15°F |
| Current Drought Conditions | Normal |