Montréal Weather in September

Montréal in September sees high daytime temperatures of 22°C (72°F) and nighttime lows of 11°C (52°F). Rainfall is fairly high this month at around 102 mm (4 in), so pack a rain jacket to stay dry.

Rainfall in Montréal in September

You can expect rain on around 11 days based on historical patterns, with 102 mm (4 in) average for the month. When it rains this month, it tends to come down fairly heavily. Showers can be substantial even if they don't last all day.

Temperature in Montréal in September

Daytime temperatures in Montréal reach 22°C (72°F) in September, dropping to 11°C (52°F) at night. This kind of day-to-night contrast is typical for this time of year. Nights cool down to 11°C (52°F), so a light jacket or extra layer is useful once the sun goes down. On the plus side, the cooler nights make for comfortable sleeping conditions.

Sunshine in Montréal in September

The area enjoys a balanced 183 hours of sunlight, ensuring it's neither too overcast nor too sunny.

Wind Speed in Montréal in September

Average wind conditions reach 5 m/s (10 knots) in September. This creates lively weather with fresh winds that make small trees sway noticeably. Remember this is an average: some days are less windy while others have particularly active windy conditions.

Average water temperature in September

The water sits at 20°C (68°F), which is a nice temperature for swimming. Not too cold, not too warm — most visitors are happy to spend time in the water.

If your ideal day consists of dry skies and pleasant temperatures, May, June, July, August and September typically offer the best circumstances for Montréal.

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For a detailed overview over the year and the best time to visit Canada, check out our Montréal's climate page.

Montréal Temperature in September

Min Temperature 11°C (52°F)  

Max Temperature 22°C (72°F)  

Water Temperature 20°C (68°F)  

Chance of Rain 38%  

Precipitation 102 mm (4 in)  

Rainy days 11 days  

Humidity 60%  

Windspeed 5 m/s (10 knots)  

Sunshine 183 hours  

Percentage Sunshine 49%  

Daily Historical Temperatures

50-year average (1976-2025)

Based on our historical records, temperatures in Montréal typically drop from around 23°C (73°F) at the start of September to approximately 18°C (64°F) by the end. Nights are cool, with lows typically ranging from 8°C (46°F) to 14°C (57°F).

Average temperatures in September

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Daily Historical Precipitation

50-year average (1976-2025)

Average daily rainfall for each day of the month based on long-term records.

Average precipitation in September

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‹ January February March April May June July August September October November December ›

Historical weather for Montréal in September

Browse day-by-day weather records for Montréal spanning 51 years. Select any month and year to see actual temperatures, rainfall, and conditions recorded on each day.

Historical weather Temperatures Precipitation

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‹ January February March April May June July August September October November December ›

Montréal historical weather extremes in September

Our historical data for Montréal spans 1976 to 2025, revealing these weather extremes.

• On September 9, 2002, temperatures climbed to 33°C (91°F), marking the warmest September day on record.
• Montréal registered its coldest September night on September 29, 1980, with temperatures dropping to -3°C (27°F).

What to Wear in Montréal in September

Comfortable temperatures call for an easy wardrobe in September. Pack summer basics like t-shirts and shorts, but include a light jacket for cooler moments. A pair of comfortable walking shoes is essential. Expect heavy rainfall, so bring good rain protection and waterproof bags. Expect water temperatures of around 20°C (68°F), which is ideal for taking a refreshing dip. Bring swimwear and consider packing a towel for drying off. Sunglasses could come in handy during the sunnier parts of your trip.

What To Do in Montréal in September

We rated the following activities from 1 (least suitable) to 10 (best) to do.

Swimming

6/10

Cycling

9/10

Walking

9/10

Camping

6/10

Outdoor sports

9/10

Select a Month

Check the conditions for any month of the year.

• January
• February
• March
• April

• May
• June
• July
• August

• September
• October
• November
• December

For a detailed overview over the year and the best time to visit Canada, check out our Montréal's climate page.

More climate data for Montréal

Temperature Rainfall Sunshine Humidity Wind Speed Water Temp

See the full Montréal climate overview or explore weather in Canada.