What I Wear for Cool- Open Water Swims

When It’s Not Quite Cold

The water is no longer warm — or hasn’t warmed up yet — but it isn’t truly cold either. Honestly, this is where a lot of my swims fall. You don’t feel shocked getting in, but you notice the temperature immediately. Long swims feel different. Short swims without a wetsuit are tempting. And deciding what to wear becomes less about rules and more about judgment.

The “In-Between” Conditions

Cool-water swims are tricky because they sit in the middle. It’s easy to over-dress and overheat, but it’s just as easy to under-dress and cut a swim short because you’re uncomfortable.

For me, this phase usually shows up when:

- I can swim comfortably for a while without insulation

- But staying in longer requires more thought

- And conditions vary day to day depending on wind, sun, and duration

In addition to thinking in temperatures, I pay attention to how long I want to swim and how I want to feel when I’m done.

The Main Decision: Full Suit or No Wetsuit

This is the decision that matters most in cool water.

I ask myself a few simple questions before every swim:

- Am I planning to be in the water briefly or for a long time?

- Do I want to swim continuously, or stop and regroup?

- Do I want to feel warm, or just not cold?

In these conditions, I’m usually deciding between:

- A full wetsuit

- A sleeveless wetsuit

- Or no wetsuit at all

There’s no single right answer — and that’s the point.

What I Actually Wear

For cool-water swims where I want to stay in the water comfortably, I most often choose a full wetsuit that prioritizes mobility and balance.

I’m not looking for something that makes me feel “sealed off” from the water. I want warmth and buoyancy, but I still want to feel connected to my stroke and my breathing.

On days when the water feels manageable but I know I’ll be swimming longer, this is what allows me to relax into the swim rather than constantly checking in with how cold I feel.

When I Go Sleeveless Instead

 On brighter days, shorter swims or slightly warmer water — I sometimes choose a sleeveless wetsuit.

Sleeveless suits are useful in this in-between phase because they:

- Offer buoyancy and light insulation

- Reduce shoulder fatigue

- Feel less mentally “committed” than a full suit

I often reach for my sleeveless wetsuit when I want flexibility without fully gearing up.

There’s also no need to purchase both a sleeveless and a full-sleeve wetsuit. I started out with only a sleeveless wetsuit, and that’s all I had for many years. I have both now — but that came more than ten years into open water and triathlon swimming.

What I Don’t Wear (Yet)

Just as important as what I wear is what I don’t.

In these conditions, I skip:

- Gloves 

- Thermal cap

- Thermal booties

- Anything that feels like over-insurance

Adding too much too early can make swimming feel heavy or disconnected. I’d rather shorten a swim slightly than feel bundled and distracted the entire time.

Restraint matters here.

Final Thoughts 

Cool-water swimming is the norm in many locations, and these temperatures reward attention and self-awareness. The goal isn’t to tough it out or dress for worst-case scenarios. It’s to choose what allows you to swim well today — and to come back tomorrow wanting to do it again.

For a more general overview of how clothing choices shift across conditions, I share that context in What to Wear in Warm, Cool, and Cold Water.

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