Here's the thing: depends on the day. Two days ago, my baby was wearing a short-sleeved onesie and light cotton pants. My girls were in shorts and t-shirt. Today I put baby in long-sleeve onesie, pants, socks, and wrapped a light blanket around him when I went outside. Girls wore jeans and long-sleeves.
I don't think you will need more than long-sleeves and a hoodie. But also to be prepared (and depending on the length of your stay) you will need to have short sleeves, shorts, and shoes like crocs or sandals, etc. You just never know here!!