Yes

you do need a jacket based on the weather in Leipzig, Germany 1 second ago

Why? Because it's cool. Pleasantly cool, but cool and it's fairly windy outside!

54°F12°C & Partly Cloudy

Wind is 11 mph18 km/h from the Northeast, gusting to 21 mph34 km/h

Date	Low	High	Wind	Day	Night
May 4	42°F5°C	56°F13°C	10 mph16 km/h from Northeast	Mostly Cloudy	Partly Cloudy
May 5	36°F2°C	59°F15°C	5 mph8 km/h from North	Mostly Clear	Mostly Cloudy
May 6	44°F7°C	58°F15°C	6 mph10 km/h from Northeast	Mostly Cloudy	Mostly Cloudy
May 7	42°F5°C	56°F14°C	11 mph17 km/h from Northeast	Mostly Cloudy	Partly Cloudy
May 8	38°F3°C	57°F14°C	9 mph14 km/h from Northeast	Mostly Clear	Mostly Clear
May 9	38°F4°C	59°F15°C	6 mph10 km/h from North	Partly Cloudy	Partly Cloudy
May 10	42°F5°C	59°F15°C	6 mph10 km/h from Northeast	Mostly Cloudy	Partly Cloudy

Low of 37°F3°C, High of 59°F15°C
Wind: 5 mph8 km/h
Precipitation: None