Wetsuit combination for Bahamas in November

[Mortis65]

I'd like some input to see if I can do a liveaboard dive week with what I have, or if I have to go out and purchase a new wetsuit.
I've been reading some wildly different forecasts for water temp in Bahamas in the Nov/Dec window, anywhere from high 70's to as low as 69.
I've read more than a few places that a 5mm full suit is the way to go, but, I just am not ready to pay that much for a suit that won't see a lot of water time.
When I'm up in Canada, I dive my dry suit all the way down into the upper 30's. I have an old 7mm + 7mm Hooded vest that I've retired that I used to wear before I went dry.
When I'm on Cozumel, I dive my 3mm shorty 79-81 degree water quite happily, or I'll dive my 3/2 full suit if I'm around fire coral etc.
Here is what I'm thinking for Bahamas in late November. Drysuit, or 7mm full suit are just too much. 3mm shorty, or 3/2 full suit are not enough.
BUT, I'm thinking I could layer my shorty under my 3/2 as a core warmer, and take my 5mm hood from my dry suit if I need some more warmth.

Am I nuts, or could I possibly have a good combination?

Thanks.

 

[randpchi]

That should work. I have dived a Lob in the Bahamas in Nov with a 3/2 fullsuit and a lavacore shirt. You can expect temps in the high 60's at times. Avg should be mid 70's. Maybe use your 7 ml vest as a layer. Have fun.

 

[Epic Diving]

The water is typically still in the mid to high 70s during November/December. There are occasionally some colder days, but not the usual. The air temp can be pretty chilly though, so the combination of long/frequent dives and cold surface intervals could catch up to you. I do use a 5mm year round, usually with a thin hood. If you're used the the cooler water temps like you say, I think the layering idea would be perfectly fine, as long as the fit is good. If you feel really restricted by the layers, or cold without it, it could put a damper on your trip. I've seen the Neosport 5mm full suits as low as $95.

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