Ottawa Weather in September
Canada · 30-year monthly averages
🌟 Great time to visit
September in Ottawa is pleasantly warm, with average daytime highs around 21°C (70°F) and nighttime lows near 10°C (50°F). Expect roughly 87mm of precipitation spread over about 9 rainy days, with a moderate amount of rain.
Avg high
21°C
70°F
Avg low
10°C
50°F
Rainfall
87mm
moderate
Rainy days
9
days with ≥1mm
🎒 What to pack
- light layers
- comfortable walking shoes
September vs the rest of the year
FAQ
- How hot is Ottawa in September?
- September in Ottawa is pleasantly warm, with average daytime highs around 21°C (70°F) and nighttime lows near 10°C (50°F). Expect roughly 87mm of precipitation spread over about 9 rainy days, with a moderate amount of rain.
- Does it rain a lot in Ottawa in September?
- Ottawa sees around 87mm of precipitation in September on average — moderate by global standards.
- Is September a good time to visit Ottawa?
- September is one of the best months to visit Ottawa — comfortable temperatures and manageable rainfall.