Ottawa weather in September 2021

Get the latest coronavirus (COVID-19) updates for Canada with current travel advice, statistics and online resources.

  • 20°C maximum daytime temperature in September in Ottawa20
    20°C max day temperature
  • 6 hours of sunshine per day
  • 12 days with some rainfall in September in Ottawa12
    12 days with some rainfall
  • 9°C minimum night-time temperature in September in Ottawa9
    9°C min night temperature
  • 12 hours of daylight per day in September in Ottawa12
    12 hours of daylight per day
  • No heat & humidity in September in Ottawa0
    No heat & humidity
  • 80 mm monthly rainfall in September in Ottawa80
    80 mm of monthly rainfall
  • UV (maximum) index 5 (Moderate) in September in Ottawa5
    5 (Moderate) UV index

Recommended for Ontario

  • Top deals & discounts
  • Ottawa weather overview
  • Ottawa climate averages by month
  • More destinations
  • Best time to go to Ottawa
  • Ottawa 5-day weather forecast

Jan Feb Mar Apr May Jun Jul Aug Sep Oct Nov Dec

The September weather guide for Ottawa, Ontario shows long term weather averages processed from data supplied by CRU (University of East Anglia), the Met Office & the Netherlands Meteorological Institute. Find out more about our data sources.

  • Save EXTRA 10% on 3-5* hotels worldwide with Priceline
  • Discount available on Pay Now & Express Deal Hotels
  • Book hotels for 2 nights or more. Not combinable
Show discount codeShow discount code ******020

Expires at 23:59 on Monday 30th Nov 2020 · View all Priceline offers

PricelineHotel deal finder

How hot is it in Ottawa in September?

Daytime temperatures usually reach 20°C in Ottawa in September, falling to 9°C at night.

How sunny is it in Ottawa in September?

There are normally 6 hours of bright sunshine each day in Ottawa in September - that's 46% of daylight hours.

Does it rain in Ottawa in September?

There are usually 12 days with some rain in Ottawa in September and the average monthly rainfall is 80mm.

Ottawa sunrise & sunset times for September 2021

Browse the sunrise & sunset times for Ottawa in September 2021. Select a month to view Ottawa sunrise & sunset times for the next twelve months.

JanFebMarAprMayJunJulAugSepOctNovDec

Date Sunrise times Sunset times
Wednesday, 1st September 2021 06:25 19:40
Wednesday, 15th September 2021 06:42 19:13
Thursday, 30th September 2021 07:00 18:44
  • Save EXTRA 10% on 3-5* hotels worldwide with Priceline
  • Discount available on Pay Now & Express Deal Hotels
  • Book hotels for 2 nights or more. Not combinable
Show discount codeShow discount code ******020

Expires at 23:59 on Monday 30th Nov 2020 · View all Priceline offers

PricelineHotel deal finder

Metric (°C / mm)  |  Imperial (°F / inches)

Back to top

Discover more about Canada

Where is hot in Ontario in September for 2021/2022?

Below are average maximum temperatures at popular destinations in Ontario in September. Select a destination to see more weather parameters.

More destinations & map >>

Related posts

Popular travel offers

Top ^

*affiliate links: find out how we are funded and why this helps us remain free to use.