Yes

you do need a jacket based on the weather in Ottawa, ON, Canada 1 second ago

Why? Because it's cold enough to freeze the brass off a bald monkey
30°F-1°C & Clear

Wind is 5 mph8 km/h from the NW, gusting to 13 mph21 km/h
March 29
7am30°F-1°C6 mph9 km/h NWClear
8am31°F-1°C6 mph10 km/h NWClear
9am33°F1°C8 mph13 km/h NWClear
10am36°F2°C9 mph15 km/h NWClear
11am38°F3°C9 mph15 km/h NWPartly Cloudy
12pm41°F5°C10 mph16 km/h NWPartly Cloudy
1pm43°F6°C10 mph17 km/h NWPartly Cloudy
2pm44°F7°C11 mph18 km/h NWPartly Cloudy
3pm46°F8°C12 mph19 km/h NWPartly Cloudy
4pm46°F8°C12 mph20 km/h NWMostly Cloudy
5pm45°F7°C12 mph20 km/h NWMostly Cloudy
6pm44°F7°C12 mph19 km/h NWPartly Cloudy
DateLowHighWindDayNight
March 2930°F-1°C46°F8°C10 mph16 km/h from NWPartly CloudyMostly Clear
March 3028°F-2°C45°F7°C9 mph15 km/h from NWMostly ClearMostly Cloudy
March 3130°F-1°C48°F9°C8 mph13 km/h from WPartly CloudyPartly Cloudy
April 130°F-1°C51°F11°C4 mph6 km/h from NEMostly CloudyMostly Cloudy
April 233°F1°C49°F9°C11 mph17 km/h from EMostly CloudyRain
April 332°F-0°C38°F3°C14 mph23 km/h from ERainSnow
April 432°F-0°C41°F5°C12 mph20 km/h from NSnowPartly Cloudy

Yes

Low of 28°F-3°C, High of 45°F7°C
Wind: 9 mph15 km/h
Precipitation: None

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