Question Newbie: Worried about water temperature

[TheRealScubaSteve]

I favor having your own wetsuit as rentals are often very worn and/or lacking a good fit.

When traveling I always bring a couple extra layers in case I feel cold. A vest (with or without hood) has saved me from cold on repetitive dives several times. For warmer locations, where you may not want a thick hood, thin hoods (caps? not sure what the proper name is) is helpful for adding some warmth. They secure with a chin strap rather than typical hood over the neck.

As mentioned above, Lavacore or Sharkskin are great layers to add. They work well and are thin and light for checked bags. I've not tried Lavacore, but love my Sharkskin. Lycra skins are nice for ease of wetsuit donning, but I don't find them to add much warmth.

When I am nervous about cold, I will usually opt for the next thickness suit I have, including boots. If you get warm, you can always flush the suit or leave zip partly open. I dove a 2.5 and 3 mil in the Keys, but I ended up adding a vest with cap towards the end of the trip.

 

[Damselfish]

Yeah not much thermal protection from Lycra, but it's between you and a rental that lots of people have worn, and can help a wetsuit slide on. On it's own can provide skin and sun protection, nice if you also do some snorkeling. Plus cheap and practically no space to pack. I find them useful.

If you dive in just Lycra, even though not providing much warmth, it buffers the little chill when you enter the water.

 

[PapaRod]

Here’s a link to a daily weather updates from Key Largo

Current Key Largo Diving Weather Report Tue, Dec 10, 2024 | Rainbow Reef Dive Center | Key Largo, Florida Keys

December 10, 2024 Numerous diving and diving related weather and condition reports for Key Largo, including Molasses Reef Tower, all centralized on one page for easy access

www.rainbowreef.com

Temperature is very subjective, when you get there you will probably find some people just diving in a bathing suit, and others wearing 5mm wet suit, I use a dive skin, for rash guard, my wife uses a skin, and a 3mm wetsuit. As others have said, a hood, or hooded vest, might be helpful

 

[TMHeimer]

i cannot imagine needing more than a 5mm in florida. as stated above, a hood is always a great add on and is easy to carry when travelling. some divers just don't like them because they are not used to them.
buying your own is the best idea. i say this because the fit of a suit is the most important thing.
if you get a thicker suit thinking it will be warmer, but it does not fit properly (loose), then it is useless.
now you know why divers have so much gear. haha depending where you are diving you may need a full 3mm, a full 5 or 7mm, a hood, drysuit, etc etc.
i currently have 3 wet suits and 3 dry suits. lol

Even I needed more than a 5 mm some winters on the panhandle (and I imagine East Coast N. Florida as well). The odd winter though I was in my shorty-- the N. shore of the Gulf can vary a lot from year to year.

 

[anchochile]

I find that dive ops (especially in warm water locales) tend to rent out the minimal wetsuit for the conditions.

For example - in 80-82 degree water, they'll usually rent out shorties, but I need a 3mm full-length to be comfortable

In 78-80 degree water (Hawaii in the summer/fall), they'll rent out 3mms, but I need a 5mm to avoid getting cold with repetitive hour-long dives.

The worst I experienced was the area around Padang Bai and Nusa Penida (Bali) where cold upwelling means temps at depth are often in the low 70s or even upper 60s. I went with a highly regarded top dive op there that only rented out shorties and tattered 3mm suits with ripped seals and holes. Those temps are really 5mm or even 7mm territory.

My point is that if you are someone like me who gets cold in a 3mm suit when the water is 79-80 degrees, you are going to want to learn your own temperature tolerances and invest in your own wetsuits so that you will always have a suit that will keep you warm for the conditions where you are diving.

I learned that lesson after experiencing 69F water in Bali while wearing a busted-up 3mm rental suit. Never again!

Fast forward to the next year, Winter in Cozumel, diving with Aldora. Water temps 80 degrees. Dives often 70-90 minutes due to their large tanks. I got some laughs on the boat for bringing my 5mm suit. But at the end of the 2nd 80-minute dive of each day, I was the only diver not complaining about freezing their butt off.

 

[Seaweed Doc]

Lots of good advice above.

One tip if you try a wetsuit hood. These sometimes cover a lot of your face. You really need to be careful to get your mask skirt under the hood, or your mask will leak. Frankly, I'd suggest practicing some mask drills in confined or very shallow open water with a new hood, especially if you're a newer diver. Removing and replacing a mask with a hood can be challenging at first, given you have to get the skirt under the hood.

 

[jadairiii]

One great option is to just buy a hooded vest, get it a tad larger so it will fit on the outside of whatever rental suit you get. I have an older version of this one from Aqua Lung. I've worn it over just a rash guard, over a shorty and over a farmer jon/short. It is quite versatile. It can take a bad wet suit and make it nice! (dont know why it says womans vest, its a mans vest on the website)

AquaFlex 6/5/3mm Hooded Wetsuit Vest Womens - Aqualung

The Aqualung wetsuit hooded vests are made with various thicknesses of Super-stretch neoprene to provide maximum insulation in high heat-loss areas.

us.aqualung.com

 

[Divin'Papaw]

For Key Largo, Rainbow Reef always lists the current water temps on the top of their website. Those would be typical diving depth temps, not the surface temp. The temp they list will be from the 40-60' range I believe. If you're not sure, just call them or whichever dive operator you will be using.

Scuba Diving Florida Keys | Rainbow Reef Dive Center | Key Largo, FL

January 7, 2025 A short drive from Miami, we're a PADI 5 Star CDC with the best coral reef, wreck, wall and night diving in the tropical Florida Keys

www.rainbowreef.com

 

[rick00001967]

Even I needed more than a 5 mm some winters on the panhandle (and I imagine East Coast N. Florida as well). The odd winter though I was in my shorty-- the N. shore of the Gulf can vary a lot from year to year.

i believe the op said they were going to the keys

 

[carrythatweight]

I second what @Seaweed Doc has noted. I am currently in Hawaii and have been diving between 15-80ft on a single tank with a 3mm full wetsuit, 3mm hood, and 6.5mm boots. The hood makes a big difference in overall warmth, at least for me. It makes wearing a mask more comfortable, especially if have long hair and/or are not using a slap or ski-goggle-style strap. It also helps to protect your neck when using a long-hose setup with Miflex hoses--I won't get into that, however. Be sure to get a hood with a few small holes at the top so that trapped air can find a way out. You can also do this (carefully) with a soldering iron, as I've seen a few divers do.

For what it's worth, I wear a Fourth Element Proteus II 3mm wetsuit. Fourth Element claims that the warmth of the Proteus II 3mm rivals 5mm wetsuits from other (unspecified) brands. I can't verify this but I wouldn't be surprising if the claim is true. They also sell what's called the Thermocline hooded vest, which you could wear as an underlayer for temps slightly colder than what you're/will be used to diving. Hope this helps. Cheers.