Yes

you do need a jacket based on the weather in Westfield, NJ 07090, USA 1 second ago

Why? Because it's not very warm out.
57°F14°C & Mostly Cloudy

Wind is 6 mph10 km/h from the E, gusting to 14 mph22 km/h
April 30
2am57°F14°C7 mph11 km/h EMostly Cloudy
3am56°F13°C7 mph11 km/h ECloudy
4am55°F13°C7 mph11 km/h ECloudy
5am54°F12°C7 mph11 km/h ECloudy
6am54°F12°C6 mph10 km/h ECloudy
7am54°F12°C7 mph12 km/h ECloudy
8am54°F12°C8 mph13 km/h ECloudy
9am56°F13°C8 mph13 km/h ECloudy
10am57°F14°C8 mph12 km/h ECloudy
11am59°F15°C7 mph12 km/h ECloudy
12pm62°F17°C8 mph13 km/h ECloudy
1pm65°F18°C8 mph13 km/h EMostly Cloudy
DateLowHighWindDayNight
April 3054°F12°C69°F21°C8 mph12 km/h from ECloudyDrizzle
May 153°F12°C73°F23°C5 mph7 km/h from SEPartly CloudyPartly Cloudy
May 251°F10°C79°F26°C5 mph9 km/h from SWMostly CloudyPartly Cloudy
May 348°F9°C62°F17°C8 mph13 km/h from EMostly CloudyMostly Cloudy
May 446°F8°C59°F15°C8 mph13 km/h from SEMostly CloudyRain
May 547°F8°C58°F14°C7 mph12 km/h from SERainMostly Cloudy
May 653°F12°C75°F24°C7 mph12 km/h from WMostly CloudyMostly Cloudy

Yes

Low of 54°F12°C, High of 73°F23°C
Wind: 5 mph7 km/h
Precipitation: 21% rain

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