Tecumseh, Ontario climate data is summarized below. Average annual temperatures range from 42.7 °F (low) to 57.7 °F (high). Annual precipitation averages 23 Inches. Tecumseh is located in USDA Plant Hardiness Zone 7a. The growing season typically runs from the last frost around Apr. 21 - Apr. 30 through the first frost around Oct. 21 - Oct. 31.
| Month | Avg. Low | Avg. High | Avg. Precip |
|---|---|---|---|
| January | -21.8 °F | -18.2 °F | 457.2 in. |
| February | -22.1 °F | -18.2 °F | 228.6 in. |
| March | -18.7 °F | -13.9 °F | 990.6 in. |
| April | -15.5 °F | -10 °F | 1422.4 in. |
| May | -11.9 °F | -6.3 °F | 1752.6 in. |
| June | -8.7 °F | -3.4 °F | 2006.6 in. |
| July | -7.4 °F | -2.2 °F | 1854.2 in. |
| August | -7.7 °F | -2.8 °F | 1600.2 in. |
| September | -10.1 °F | -5.1 °F | 1651 in. |
| October | -13.4 °F | -8.8 °F | 1041.4 in. |
| November | -16.9 °F | -12.8 °F | 1092.2 in. |
| December | -19.5 °F | -16.4 °F | 736.6 in. |
| Annual | 42.7 °F | 57.7 °F | 22.98 in. |
| Average First Frost Date | Oct. 21 - Oct. 31 |
| Average Last Frost Date | Apr. 21 - Apr. 30 |
| Average Days With Frost | 100-125 Days |
| Plant Hardiness Zone | Zone 7a : 0°F to 5°F |
| Current Drought Conditions | Normal |