Verdict: Excellent month
Montréal Weather in September
September hits the sweet spot in Montréal — highs around 21°C (70°F), ideal for a full day on foot. Rain is occasional — about 8 wet days in a typical year. Overall, September is one of the best months of the year to be in Montréal.
Average high
21°C / 70°F
Average low
13°C / 55°F
Rain days
~8
Precipitation
80 mm
What to pack for Montréal in September
- Layers — t-shirts under a light jacket or sweater
- A packable rain shell or compact umbrella earns its space
- Comfortable walking shoes — every guide on this site assumes you'll use them
September against the rest of the year
Warmest in Montréal: Jul (27°C / 81°F) · Coolest: Jan (-4°C / 25°F) · Wettest: Aug (~14 rain days)
-4°
-12°
Jan
-2°
-12°
Feb
4°
-5°
Mar
12°
1°
Apr
20°
9°
May
25°
15°
Jun
27°
18°
Jul
25°
17°
Aug
21°
13°
Sep
15°
7°
Oct
7°
0°
Nov
1°
-6°
Dec
Daily highs / lows in °C · bars show rain days per month · ERA5 climate normals (2020–2024)