evlPanda said..That's beautifully mordant but ultimately a vague answer. How about inside a bay?
I've experienced board shorts and rashie on a Saturday in the ocean, and then so cold I can't talk in a 3mm steamer on Sunday in the bay.
Sounding like sun and a northerly = boardies and a top.

Lets just say I was very cold a week ago in a southerly (with a full steamer) but a week before that I was in 3mm neo vest and boardies even for the 6am surfs. Tomorrow - no full wetsuit needed IMO (in the ocean, Narra lake will be colder).
Sorry about the LMGTFY - always makes me laugh.
Fingers crossed Longy/Collaroy will work.