Skip 5mm and go to 7mm?

[NAUI Wowie]

Great question! Thickness does help keep the diver warm, but if cool water is flushing in to the suit you'll get cold no matter how thick.

I would highly (and I mean highly) suggest you get a custom fit wetsuit. I dive a lot in California where it's between 50 and 75 degrees F, and I comfortably dive a 5mm fullsuit with attached hood year-round, and add a vest underneath when it's coldest. I have tried many wetsuit styles and this one works best for me.

I get my suits from JMJ Wetsuits, and they are *very* helpful - you should give them a call with your questions and take their recommendations - they know what they're doing and have helped tons of divers solve design challenges and made them great suits.

Hope that helps!
Derek

I dive channel islands etc in warm weather. I would NEVER use a 5mil lol thats freezing to death . even a 7 mil multiple dives a day in CA is a NO for me. I use a 8/7 or 9/8 semi dry for CA waters. no matter the month or area

 

[Derek of So Cal]

I dive channel islands etc in warm weather. I would NEVER use a 5mil lol thats freezing to death . even a 7 mil multiple dives a day in CA is a NO for me. I use a 8/7 or 9/8 semi dry for CA waters. no matter the month or area

Well @NAUI Wowie, everyone is different. To be fair, I am trying to push the custom wetsuit factor because fit does make a huge difference and I think there are many wetsuit divers that don't get it because they've only dived stock sizes. That said, if you prefer to dive thick suits then you prefer to dive thick suits! Everybody has their thing and I'm just sharing with the OP what works really well for me.
Have a good one,
Derek

 

[Still Kicking]

skip the 5 and 7mm and go straight to a drysuit.

Own a 3mm and a drysuit and you're covered for all temperature ranges.

There's a place and a time for a drysuit but they add another layer of complexity (leaks, torn seals, extra drag etc) that you avoid completely with wetsuits. A well fitted 5mm and/or 7mm bridge a broad temperature range without the hassle of a drysuit.