When to go · Ottawa
Ottawa in September
Great month. Inside Ottawa's best window: May–Jun, Sep–early Oct.
Key facts
- Verdict
- Great
- Temperature
- 21°C (70°F)70°F (21°C) / 10°C (50°F)50°F (10°C)
- average high / low
- Rain days
- 11
- Crowds
- Medium
- Canada overall
- Prices
- Medium
- Canada overall
Verdict
Inside Ottawa's best window: May–Jun, Sep–early Oct.
Is another month better than September?
No other month rates higher than September for Ottawa in this guide.
Weather in September
- OttawaHighs around 21 °C (70 °F), lows around 10 °C (50 °F), rain on about 11 daysHighs around 70 °F (21 °C), lows around 50 °F (10 °C), rain on about 11 days
- Ontario and Great Lakes, Canada · Toronto, Ottawa, Niagara Falls, Algonquinbest weather
Humid summers, snowy winters; late September–October foliage in Algonquin.
Crowds and prices
- Crowds · Canada overall
- Medium
- Prices · Canada overall
- Medium
Canada overall: After Labour Day crowds drop; larches turn gold in the Rockies late in the month.
Compare two months
Weather, crowds and prices for any two months in Ottawa, side by side.
Verdict
Sep: Great
May: Great
Daytime high
Sep: 21 °C (70 °F)70 °F (21 °C)
May: 19 °C (66 °F)66 °F (19 °C)
Night low
Sep: 10 °C (50 °F)50 °F (10 °C)
May: 8 °C (46 °F)46 °F (8 °C)
Rain days
Sep: 11 (better)
May: 12
Crowds
Sep: Medium
May: Medium
Prices
Sep: Medium
May: Medium
Festivals listed
Sep: 0
May: 0
September: Inside Ottawa's best window: May–Jun, Sep–early Oct.
May: Inside Ottawa's best window: May–Jun, Sep–early Oct.
Ottawa: figures are long-term averages from this guide, not a forecast.
What to pack
- A warm layer for the evenings
- A rain jacket or umbrella and shoes that dry fast