Season?

[MrVegas]

In October? What water temps? I dove a 7mm with a 5/3 hooded vest, xs scuba dry 5 gloves, neoprene socks and 7mm booties reasonably comfortably to 55F, and would start getting pretty cold after that. My coldest wet dive was 47F -- I didn't feel cold, I just didn't feel much at all, which probably wasn't good.

As someone else said, doing one dive, even a longish one, might be fine, but getting back in for the second one is tough, especially if the air temperature is cold. I really like a nice October day for diving, though. (And now I have drysuit.)

 

[Byrdie]

As mentioned and to reiterate, individual tolerance is different. I have the same 7mm Thermax and am good for temperatures ~52 for ~30 minutes. Anything colder or longer I go dry suit. Hope this is helpful.

 

[Esprise Me]

I'm on the less-cold-tolerant side of the bell curve, but I can comfortably wear my Henderson 7mm one-piece wetsuit down to about 60 F, with some caveats:
- the air has to be at least as warm, and it can't be windy unless it's really hot
- one dive is much more comfortable than two or three
- even at 60 degrees, I can get pretty chilled below 60 feet due to wetsuit compression
- a hood is a must, and a Sharkskin jacket (neutrally buoyant but the warmth equivalent of another mm or two of neoprene) is also really helpful, especially since my wetsuit isn't a perfect fit and doesn't have a great seal around the neck

Everyone's different, and you'll figure out your personal threshold as well as how cold the water actually gets as you go along. But if you want to extend your diving season, a drysuit is a great investment. It's especially helpful on those days when the air is cold and I want to dive more than once, and when I want to go deep.