Yes

you do need a jacket based on the weather in Recoleta, Buenos Aires, Argentina 3 minutes ago

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

Wind is 7 mph12 km/h from the West, gusting to 17 mph28 km/h
May 10
6am58°F14°C8 mph13 km/h WestClear
7am58°F14°C8 mph14 km/h WestMostly Clear
8am59°F15°C8 mph14 km/h SouthwestClear
9am61°F16°C8 mph13 km/h SouthwestClear
10am64°F18°C8 mph13 km/h SouthwestClear
11am67°F19°C8 mph13 km/h SouthwestClear
12pm69°F20°C8 mph12 km/h SouthwestClear
1pm70°F21°C7 mph12 km/h SouthwestClear
2pm71°F22°C7 mph11 km/h SouthwestClear
3pm70°F21°C6 mph10 km/h SouthwestClear
4pm69°F21°C5 mph8 km/h SouthwestClear
5pm67°F20°C4 mph6 km/h SouthClear
DateLowHighWindDayNight
May 957°F14°C71°F22°C7 mph11 km/h from SouthwestClearClear
May 1056°F14°C69°F20°C8 mph12 km/h from NortheastClearMostly Clear
May 1156°F13°C68°F20°C8 mph14 km/h from NortheastPartly CloudyClear
May 1258°F15°C70°F21°C7 mph12 km/h from NorthMostly ClearMostly Cloudy
May 1363°F17°C73°F23°C6 mph9 km/h from NorthMostly CloudyRain
May 1465°F18°C71°F22°C8 mph13 km/h from EastRainThunderstorms
May 1565°F18°C73°F23°C7 mph11 km/h from NorthThunderstormsThunderstorms

Yes

Low of 56°F14°C, High of 69°F21°C
Wind: 8 mph12 km/h
Precipitation: None

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