Yes

you do need a jacket based on the weather in Québec City, QC, Canada 31 seconds ago

Why? Because just cool enough for a jacket, but not warm enough to ditch it!
53°F12°C & Mostly Clear

Wind is 2 mph4 km/h from the Northeast, gusting to 3 mph5 km/h
August 5
6am53°F12°C3 mph5 km/h NortheastMostly Clear
7am56°F13°C2 mph4 km/h NortheastMostly Clear
8am60°F16°C3 mph5 km/h NortheastMostly Clear
9am63°F17°C5 mph8 km/h EastClear
10am66°F19°C7 mph11 km/h EastMostly Clear
11am68°F20°C8 mph13 km/h EastMostly Clear
12pm70°F21°C8 mph13 km/h EastClear
1pm72°F22°C7 mph11 km/h EastMostly Clear
2pm73°F23°C7 mph10 km/h EastMostly Clear
3pm74°F23°C7 mph11 km/h EastClear
4pm74°F23°C7 mph11 km/h EastMostly Clear
5pm73°F23°C6 mph10 km/h EastClear
DateLowHighWindDayNight
August 553°F12°C74°F23°C6 mph10 km/h from EastMostly ClearClear
August 655°F13°C78°F26°C6 mph9 km/h from EastClearClear
August 756°F13°C81°F27°C2 mph4 km/h from SoutheastClearMostly Clear
August 859°F15°C80°F27°C5 mph7 km/h from SouthwestPartly CloudyPartly Cloudy
August 965°F18°C81°F27°C9 mph14 km/h from SouthwestThunderstormsMostly Cloudy
August 1068°F20°C85°F29°C7 mph12 km/h from SouthwestPartly CloudyMostly Clear
August 1171°F21°C87°F31°C6 mph10 km/h from SouthwestMostly ClearPartly Cloudy

Yes

Low of 55°F13°C, High of 78°F26°C
Wind: 6 mph9 km/h
Precipitation: None

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