Weather in Montreal in August 2025
Average weather
Average temperature in Montreal in August
The expected average maximum temperature in August is +24°C with a maximum of +27°C and a minimum of +11°C.
The average maximum temperature goes up 0% by the end of the month, compared with the beginning of the month, from +21°C to +21°C.
Is Montreal warm or cold in August?
Montreal is typically warm in August.
Maximum temperatures go down compared to the previous month from +27°C to +25°C. The minimum temperature also goes up from +17°C to +17°C.
It’s generally warm, but pack a long-sleeve shirt for evenings.
August is one of the warmest months in Montreal, here is the comparison with other months:
Climate in Montreal in August
| July | August | September | ||||
|---|---|---|---|---|---|---|
| Avg. temperature | ||||||
| +27°C | +25°C | +21°C | ||||
| Min. temperature | ||||||
| +7°C | +6°C | -3°C | ||||
| Max. temperature | ||||||
| +36°C | +35°C | +34°C | ||||
| Rainfall | ||||||
| 98 mm | 102 mm | 98 mm | ||||
| Wind | ||||||
| 3 m/s | 3 m/s | 3 m/s | ||||
| Humidity | ||||||
| 68% | 71% | 73% | ||||
| Air pressure | ||||||
| 1012 HPa | 1014 HPa | 1016 HPa | ||||
| Sunny days | ||||||
| 6 | 6 | 7 | ||||
| Cloudy days | ||||||
| 8 | 8 | 9 | ||||
| Rainy days | ||||||
| 13 | 13 | 13 | ||||
| Snowy days | ||||||
| 0 | 0 | 0 | ||||
August weather is still as good as in July. It’s getting colder in August. From +27°C in the day, the average maximum temperature lowers to +25°C. Prepare for more rain. Average rainfall goes from 98 mm to 102 mm. Humidity rises from 68% to 71%. The average wind speed doesn’t change much during August, staying around 3 m/s. The amount of sunny days stay about the same, averaging 6 sunny days during the month.
September brings much the same weather, it remains good.
Wind
The average wind speed is 3 m/s getting up to 6 m/s which is a medium breeze. You can feel it, especially getting out of the water.
The average wind speed in Montreal is gradually increasing during August, going from 3 m/s to 4 m/s over the course of the month.
Rain
How was the weather last August in Montreal?
Climate Change over Years
The climate in Montreal in August has not changed much over the last 43 years.
The average temperature was the lowest in 1980 (+10°C) and the highest in 2021 (+14°C). The driest year was 1985 with only 524 mm of rainfall, and the wettest year was 2023 with 2843 mm.
FAQ
Is August a good time to visit Montreal?
Can you sunbathe in Montreal in August?
Is Montreal rainy in August?
Is it sunny in Montreal in August?
Other cities in Canada
Monthly weather in Montreal
Source of the data
For this page, we’ve looked at the typical weather in Montreal, based on historical hourly weather data from January 1, 1979, to December 31, 2023.
For past dates, we show actual recorded data at the location at that time. Forecasts are based on recorded weather during that day of the year, averaged over the total years for which we have records (unless stated otherwise). The daily temperature is the highest recorded temperature in the shadow during that day.