Yes

you do need a jacket based on the weather in West Haven, CT 06516, USA 1 second ago

Why? Because it's cold. simple as that.
50°F10°C & Mostly Cloudy

Wind is 4 mph6 km/h from the SE, gusting to 7 mph12 km/h
April 25
1pm51°F11°C5 mph9 km/h SEClear
2pm52°F11°C7 mph11 km/h SClear
3pm53°F12°C7 mph12 km/h SClear
4pm53°F12°C8 mph12 km/h SClear
5pm53°F12°C7 mph12 km/h SClear
6pm52°F11°C7 mph11 km/h SClear
7pm50°F10°C7 mph11 km/h SClear
8pm47°F9°C8 mph13 km/h SClear
9pm45°F7°C8 mph12 km/h SClear
10pm44°F7°C6 mph10 km/h SClear
11pm43°F6°C5 mph8 km/h SClear
April 26
12am42°F5°C4 mph6 km/h SClear
DateLowHighWindDayNight
April 2537°F3°C53°F12°C6 mph10 km/h from SEClearClear
April 2637°F3°C58°F15°C6 mph9 km/h from SEClearClear
April 2739°F4°C60°F15°C8 mph12 km/h from SPartly CloudyDrizzle
April 2846°F8°C64°F18°C7 mph11 km/h from SMostly CloudyMostly Cloudy
April 2952°F11°C73°F23°C4 mph7 km/h from SEPartly CloudyMostly Cloudy
April 3050°F10°C60°F16°C8 mph13 km/h from SEMostly CloudyMostly Cloudy
May 151°F11°C74°F23°C4 mph7 km/h from SWPartly CloudyMostly Clear

Yes

Low of 37°F3°C, High of 58°F15°C
Wind: 6 mph9 km/h
Precipitation: None

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