Yes

you do need a jacket based on the weather in Copenhagen, Denmark 1 second ago

Why? Because it's quite chilly.
41°F5°C & Mostly Cloudy

Wind is 5 mph8 km/h from the W, gusting to 6 mph10 km/h
April 16
8pm40°F5°C5 mph8 km/h NWMostly Cloudy
9pm40°F4°C5 mph8 km/h NWMostly Cloudy
10pm40°F4°C5 mph8 km/h NPartly Cloudy
11pm39°F4°C5 mph8 km/h NPartly Cloudy
April 17
12am39°F4°C5 mph8 km/h NMostly Clear
1am39°F4°C6 mph10 km/h NEMostly Clear
2am40°F5°C7 mph11 km/h NEMostly Clear
3am42°F6°C7 mph12 km/h NEMostly Clear
4am44°F7°C7 mph11 km/h NEMostly Clear
5am46°F8°C7 mph11 km/h NEMostly Clear
6am48°F9°C6 mph10 km/h NEMostly Clear
7am49°F9°C5 mph8 km/h NEPartly Cloudy
DateLowHighWindDayNight
April 1639°F4°C50°F10°C6 mph10 km/h from NEMostly ClearPartly Cloudy
April 1738°F3°C52°F11°C6 mph10 km/h from NWPartly CloudyMostly Cloudy
April 1836°F2°C46°F8°C13 mph20 km/h from ECloudyMostly Clear
April 1934°F1°C49°F9°C5 mph9 km/h from WPartly CloudyPartly Cloudy
April 2038°F3°C51°F11°C6 mph9 km/h from NEPartly CloudyPartly Cloudy
April 2138°F3°C50°F10°C8 mph12 km/h from NPartly CloudyMostly Cloudy
April 2236°F2°C46°F8°C9 mph14 km/h from NWMostly CloudyDrizzle

Yes

Low of 38°F4°C, High of 52°F11°C
Wind: 6 mph10 km/h
Precipitation: 19% rain

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