Yes

you do need a jacket based on the weather in Helensburgh, UK 1 second ago

Why? Because the rain is just enough to ruin your hairstyle but not your mood and sorry, it's too cool for just a hoodie and it's so windy, you’re practically horizontal just trying to walk!
50°F10°C & Rain

Wind is 19 mph30 km/h from the West, gusting to 29 mph47 km/h
May 25
2am50°F10°C19 mph31 km/h WestDrizzle
3am50°F10°C19 mph30 km/h WestDrizzle
4am51°F11°C19 mph30 km/h WestWindy
5am52°F11°C19 mph30 km/h WestWindy
6am53°F12°C19 mph31 km/h WestWindy
7am54°F12°C19 mph31 km/h WestWindy
8am53°F11°C19 mph30 km/h WestWindy
9am54°F12°C19 mph31 km/h WestWindy
10am54°F12°C19 mph31 km/h WestWindy
11am54°F12°C19 mph30 km/h WestWindy
12pm52°F11°C18 mph29 km/h WestDrizzle
1pm52°F11°C18 mph29 km/h WestWindy
DateLowHighWindDayNight
May 2447°F8°C56°F13°C19 mph30 km/h from WestDrizzleDrizzle
May 2546°F8°C53°F11°C15 mph25 km/h from SouthwestRainRain
May 2647°F8°C55°F13°C12 mph20 km/h from SouthwestRainRain
May 2749°F10°C58°F14°C13 mph21 km/h from WestDrizzleMostly Cloudy
May 2847°F8°C59°F15°C14 mph22 km/h from WestRainMostly Cloudy
May 2949°F10°C60°F15°C5 mph8 km/h from WestDrizzleDrizzle
May 3051°F11°C59°F15°C10 mph17 km/h from SouthRainDrizzle

Yes

Low of 46°F8°C, High of 53°F12°C
Wind: 15 mph25 km/h
Precipitation: 84% rain

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