Although Montreal does enjoy four seasons, winter and summer are the most prominent. Spring is very short, and the first hints of autumn begin in mid-August. Winter starts in October and lasts until early May. The average January temperature is -18°C (-4°F).
| Month | Temp (°C) | Rainfall (mm) | Humidity (%) | Sunshine (hours) |
| Jan | -13 - -6 | 71 | ||
| Feb | -12 - -4 | 66 | ||
| Mar | -6 - 1 | 71 | ||
| Apr | 1 - 10 | 74 | ||
| May | 8 - 18 | 69 | ||
| Jun | 13 - 22 | 84 | ||
| Jul | 16 - 26 | 86 | ||
| Aug | 15 - 24 | 91 | ||
| Sep | 10 - 18 | 84 | ||
| Oct | 3 - 12 | 76 | ||
| Nov | -1 - 5 | 89 | ||
| Dec | -10 - -2 | 86 |