indonesia is very vast geographically and we have lots of volcanoes, where I live is higher up surrounded by several inactive volcanoes and more inland, so mostly drier and breezy, sun exposure is burning but the wind is fresh. the fact I'm born and acclimatized here and doesn't have much body fat helps too, basically my jacket temp is anything under 28C, at 20C probably I wear sweater under my jacket, but leather jacket is not a common outerwear here usually worn as long distance riding gear, people do rarely wear outerwear since our weather is temperate, but younger people do wear hoodies, or flannel shirts just for fashionI don't get how u can wear that in Indonesia. When I was there on a few business trips it was so hot and humid, I was sweating buckets in simple office wear lol.
The only jacket I wore in Indonesia was my diving vest.








