Ottawa Weather in August

In Ottawa, August brings very high daytime temperatures around 32°C (90°F), with nights cooling to 19°C (66°F). Expect quite a bit of rainfall this month.

Rainfall in Ottawa in August

On average, there are about 10 days with rain during this month, averaging 94 mm (3.7 in). Individual showers can be quite heavy this month. A proper umbrella or rain jacket is worth having.

Temperature in Ottawa in August

Daytime highs in Ottawa in August reach 32°C (90°F), with nights around 19°C (66°F). The hottest part of the day is usually in the afternoon, so lighter clothing can help you stay comfortable. Nights drop to around 19°C (66°F), which is noticeably cooler than the daytime. A light jacket for the evening is a sensible addition, and the cool nights tend to make sleeping comfortable.

Sunshine in Ottawa in August

There are approximately 291 hours of sunshine this month, resulting in mostly clear days.

For Ottawa itself, October generally stands out with the best circumstances. If you're seeking pleasant, dry and sunny weather somewhere else in the world, our weather planner can help you explore other options.

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For a detailed overview over the year and the best time to visit the United States of America, check out our Ottawa's climate page.

Ottawa Temperature in August

Min Temperature 19°C (66°F)  

Max Temperature 32°C (90°F)  

Chance of Rain 33%  

Precipitation 94 mm (3.7 in)  

Rainy days 10 days  

Humidity 71% *  

Sunshine 291 hours *  

Percentage Sunshine 69% *  

* Data from: Topeka, the United States of America (59 KM, 37 Miles).

What to Wear in Ottawa in August

Warm but pleasant conditions in Ottawa in August. Focus on lightweight, maybe with natural fabrics, cotton blend shirts, comfortable shorts, and breathable footwear. A light cover-up for sun protection is smart too. Expect heavy rainfall, so bring good rain protection and waterproof bags. You'll definitely want to pack sunglasses and sunscreen. There will be plenty of bright sunshine this month.

What To Do in Ottawa in August

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

Swimming

9/10

Cycling

7/10

Walking

7/10

Camping

8/10

Outdoor sports

7/10

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 the United States of America, check out our Ottawa's climate page.

More climate data for Ottawa

Temperature Rainfall Sunshine Humidity

See the full Ottawa climate overview or explore weather in the United States of America.