September 03, 2021

Open Water Swimming has magical benefits for dippers and swimmers no matter the time of year, but during the winter months it is really important to be aware of added dangers, and take extra precautions against cold water shock, and hypothermia.

Open Water temperatures in Ireland tend to dip below 10C during October or November and not rise above that number until April, or even May. It’s a long slog!

But seasoned open water swimmers will tell you that even if you only get in for two minutes per week, it’s worth it for the initial endorphins, and continued acclimatisation. After five months of short dips under 10C, the summer highs of 16C will feel positively tropical!

So if you are planning to dip in open water in Ireland this winter, follow our advice below to make it a safe and enjoyable experience.

Tips for Winter Dipping in Ireland

Know your limits

· Before you get in any body of open water, it’s vital to understand your own ability and know your own limits. If you’re unsure of your ability, ask a coach for advice, or a friend who is experienced in open water – ideally bring them swimming with you!

Check the weather and water temperature

· During winter, it’s not just wind that you have to watch out for, ice can make entry and exit points treacherous, and freezing air temperatures will severely limit your time in the water.

· If swimming in the sea, you can find rough water temperatures via the information buoys on If swimming in a lake or river, ask locals, or take a thermometer with you.

Keep as warm as you can before getting in

· It’s a common myth that you should acclimatise to the temperature before you get in water. Arrive warm, get ready to swim quickly, and do not stand around on shore in your swimming things. Just get in!

Get in slowly to avoid cold water shock

· All Irish waters are cold enough to cause cold water shock just about every day of the year, but if you are a regular open water swimmer it is more likely to catch you out in the winter.

· Cold water shock is a range of natural reactions our bodies take to protect us from cold water. These reactions begin with gasping and hyperventilating, as your blood moves towards the middle of the body in a bid to keep warm. These reactions can progress to a loss of strength and muscle control, which prevents swimming and leads to drowning.

· By getting into the water slowly, and splashing your torso and face before you immerse, you can control your breathing and help prevent more serious reactions.

For more information on cold water shock, please read the Royal Life Saving Society’s Cold Water Shock: The Facts.

Wear a watch to monitor time in water

· A watch can tell you how long you have been in and how long it will take you to get back to shore. This is crucial information for winter dippers and swimmers, should they begin to feel cold or show signs of hypothermia.

Know the signs of hypothermia

· Hypothermia creeps up slowly. It occurs when the body’s core temperature drops below 35C, and can first present in swimmers as persistent shivering, feeling cold, and having low energy.

· It's paramount that this swimmer's heat loss is reduced immediately and warmth restored gradually to ensure symptoms do not progress to more severe issues like uncontrollable shivering, confusion and loss of coordination.

· It's really important to understand the dangers of being cold, even before reaching a hypothermic stage, as if your hands are too stiff to get dressed, or you are shivering too hard to put your clothes on, or drink your tea, you risk getting colder and increasing chances of hypothermia symptoms.

· The best way to avoid this is to get out of the water before, or as soon as, you feel cold. You will learn to feel at what point this happens for you – and if you are wearing a watch you will be able to note your safe exposure time.

For comprehensive information on hypothermia symptoms, prevention measures and remedies, check out the HSE’s Preventing Hypothermia guide.

Bring extra layers for after and a hot drink, or soup

· Even the shortest open water dip in winter in Ireland will cause your body temperature to fall, and it is very difficult to warm up after swimming when the air and wind temperature is equally as low, if not colder.

· To help restore your warmth, bring extra, loose, warm layer(s) for your top half, a woolly hat, socks and gloves, and a hot drink, or even a cosy flask of soup. Pro tip: Hot water bottles are the height of winter dipping luxury!

Plan to get dressed quickly

· As soon as you get out of the water, focus on getting dressed above anything else. To be most efficient in this, as you get undressed, pack your clothes back into your bag as you take them off. Then when you go to get dressed, the first item will be the last you took off.

· Lots and lots of small, loose layers without fiddly zips and hooks are recommended. Jeans, tight leggings, and materials like lycra are not your friends after winter dips.

Exercise warms you up fastest

· The fastest way to properly warm up after you swim is exercise. A brisk walk after you have fully dressed and recovered, or running on the spot, or jumping jacks will stop the shivering in no time.

Always respect the Open Water, know your own limits and listen to advice from officials regarding weather and water conditions.

For more safety tips in open water, check out our full guide on Open Water Swimming Safety in Ireland.