Fort Frances, Ontario climate data is summarized below. Average annual temperatures range from 28.8 °F (low) to 48.1 °F (high). Annual precipitation averages 15 Inches. Fort Frances is located in USDA Plant Hardiness Zone 4a. The growing season typically runs from the last frost around May 21 - May 31 through the first frost around Sep.11 - Sep. 20.
| Month | Avg. Low | Avg. High | Avg. Precip |
|---|---|---|---|
| January | -28.8 °F | -23.1 °F | 0 in. |
| February | -28.5 °F | -21.7 °F | 0 in. |
| March | -23 °F | -16.5 °F | 76.2 in. |
| April | -18.7 °F | -12.6 °F | 355.6 in. |
| May | -15.3 °F | -8.5 °F | 1270 in. |
| June | -12 °F | -5.7 °F | 2006.6 in. |
| July | -10.5 °F | -4 °F | 2184.4 in. |
| August | -11.1 °F | -4.4 °F | 1676.4 in. |
| September | -13.5 °F | -7.1 °F | 1270 in. |
| October | -16.6 °F | -11.5 °F | 609.6 in. |
| November | -20.7 °F | -16.5 °F | 203.2 in. |
| December | -26.5 °F | -22.1 °F | 0 in. |
| Annual | 28.8 °F | 48.1 °F | 14.96 in. |
| Average First Frost Date | Sep.11 - Sep. 20 |
| Average Last Frost Date | May 21 - May 31 |
| Average Days With Frost | Over 180 Days |
| Plant Hardiness Zone | Zone 4a : -30°F to -25°F |
| Current Drought Conditions | Abnormally Dry |