Yes

you do need a jacket based on the weather in Isle of Man 1 second ago

Why? Because it's cold. simple as that.
43°F6°C & Drizzle

Wind is 7 mph11 km/h from the NE, gusting to 13 mph21 km/h
April 25
6pm42°F6°C8 mph12 km/h NEPartly Cloudy
7pm42°F6°C9 mph14 km/h NEMostly Clear
8pm41°F5°C9 mph14 km/h NEMostly Clear
9pm40°F5°C8 mph13 km/h NEMostly Clear
10pm40°F4°C7 mph12 km/h NEMostly Clear
11pm39°F4°C8 mph12 km/h NEMostly Clear
April 26
12am38°F4°C8 mph13 km/h NEMostly Clear
1am38°F3°C8 mph13 km/h NEMostly Clear
2am39°F4°C9 mph14 km/h NEMostly Clear
3am41°F5°C10 mph15 km/h NEMostly Clear
4am42°F5°C10 mph16 km/h NEMostly Clear
5am43°F6°C10 mph15 km/h NEPartly Cloudy
DateLowHighWindDayNight
April 2441°F5°C48°F9°C9 mph14 km/h from NMostly CloudyDrizzle
April 2538°F3°C47°F8°C8 mph13 km/h from NEPartly CloudyPartly Cloudy
April 2640°F4°C50°F10°C7 mph10 km/h from EMostly ClearMostly Clear
April 2739°F4°C50°F10°C9 mph14 km/h from NWMostly ClearPartly Cloudy
April 2842°F6°C51°F10°C22 mph35 km/h from SRainDrizzle
April 2945°F7°C53°F11°C16 mph26 km/h from SEDrizzleMostly Cloudy
April 3046°F8°C59°F15°C9 mph14 km/h from NEPartly CloudyPartly Cloudy

Yes

Low of 38°F4°C, High of 47°F9°C
Wind: 8 mph13 km/h
Precipitation: 10% rain

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