Grommet check your local buoy reading for your break at the time of your sesh. That'll give you the stats.
You'd have to try out different thicknesses in different temps and see what is best for you. Temp tolerance seems to be like the pain scale, subjective from one person to the next. I'm a minimalist for neoprene as I'm a furnace. But when I do rubber up, it's a properly fitting Drylock brah.