How to Sleep in Hot Weather: What really works?
- Sophie Bostock, PhD
- Jul 8
- 5 min read
Hot weather can make it harder to fall asleep, stay asleep and wake up feeling refreshed.
While a few warm nights are unlikely to cause lasting harm, understanding how heat affects sleep can help you make simple changes that improve comfort and sleep quality.
So, here are the answers to some of the questions I most frequently get asked during a heatwave. Many of these tips appear in a new feature by Antonia Hoyle.
Why does hot weather make it harder to sleep?
Our body temperature follows a natural 24-hour (circadian) rhythm. Core body temperature typically peaks in the late afternoon and gradually falls in the evening, helping signal that it is time to sleep.
To drift into deeper sleep, our bodies usually cool by around 1°C. We do this by increasing blood flow to the skin, allowing heat to escape.
However, when our environment gets too hot (above around 25°C), this process becomes less efficient and our bodies radiate less heat. As a result, it can take longer to fall asleep and sleep may become lighter and more fragmented.
Research also suggests that high temperatures can reduce deep sleep and REM sleep, both of which are important for physical recovery, memory and emotional wellbeing.
Could climate change be ruining your sleep?
I recently spoke on the BBC World Service ‘The Climate Question’ podcast hosted by Graihagh Jackson, with BBC reporter Janhavee Moole, to discuss the question ‘Could climate change be ruining our sleep?’
We explored how rising temperatures are disrupting sleep in India and beyond and share practical tips on how to stay cool in a warming world.
What is the best temperature for sleep?
There isn’t one perfect temperature for everyone, but around 18-20°C is usually considered a comfortable range for sleep. If you are fortunate enough to have air conditioning and want to know what to aim for, I would start at 18C.
How can you keep your bedroom cool?
Preventing heat from building up during the day can make a big difference at night.
Try to:
Keep curtains or blinds closed during sunny periods (blackout blinds can be particularly helpful)
Open windows to encourage airflow
Create a cross-breeze by opening windows on opposite sides of your home
Sleep on a lower floor if possible, as heat rises
Can a fan help you sleep better?
Yes. Airflow helps sweat evaporate from the skin, which is one of the body’s most effective cooling mechanisms.
Fans, open windows and air conditioning can all improve comfort. If you are using a fan and worried about just circulating warm air, placing a bowl of ice in front of it may create a cooling effect by slightly cooling the air moving across the skin.
Should you sleep naked or wear pyjamas?
The most important factor is choosing breathable materials.
Natural fibres such as cotton help wick sweat away from the body and improve airflow.
Some people find lightweight cotton pyjamas more comfortable than sleeping naked, while others prefer less clothing. Focus on comfort and breathable fabrics rather than following a one-size-fits-all rule.
What bedding is best for hot weather?
Heavy bedding can trap heat and make sleeping more difficult.
Consider:
Switching to a lower tog duvet
Using a cotton sheet instead of a duvet
Choosing natural fibre bedding
Using separate covers if you share a bed with a partner (especially if they start to feel like a furnace)
Separate bedding can help reduce heat transfer between partners and make temperature control easier.
Is a warm bath better than a cold shower before bed?
Surprisingly, yes.
A lukewarm bath or shower one to two hours before bed can help the body cool down more effectively.
When you get out of the water, your body naturally cools afterwards because warm water increases blood flow to the hands and feet, helping release heat and allowing core temperature to drop.
Cold showers may feel refreshing in the moment, but they can temporarily stimulate the nervous system and divert blood flow away from the extremities, making them less helpful when preparing for sleep.
Do cooling products work?
Some cooling products may help improve comfort at night.
Cooling gel mattress toppers and pillow liners are designed to absorb body heat and feel cooler to the touch.
Cooling eye masks may help some people relax before sleep, and research suggests forehead cooling may support sleep onset and may be particularly helpful for women experiencing hot flushes.
Although these products are unlikely to solve every sleep problem, they can be useful additions during particularly warm weather.
What else can help you sleep in the heat?
A few additional habits can support better sleep:
Stay hydrated throughout the day, especially during hot weather when we lose more fluid through sweating
Finish your evening meal at least two hours before bedtime to reduce discomfort and avoid generating excess body heat close to slee
Limit alcohol, which can contribute to dehydration and fragmented sleep
Reduce bright light exposure in the 90 minutes before bed to help support melatonin production
These habits support the body’s natural sleep and temperature-regulation processes.
Who is most affected by hot nights?
Hot weather tends to have a greater impact on:
Older adults
People experiencing perimenopause or menopause, particularly those experiencing hot flushes or night sweats
These groups may be more sensitive to temperature changes and more likely to experience disrupted sleep during heatwaves.
Should you try to catch up on lost sleep?
If you have one poor night because of the heat, try not to panic.
Research suggests that when overnight temperatures reach around 25°C, people lose an average of around 13-25 minutes of sleep per night. It can feel worse in the moment than the numbers suggest.
Rather than going to bed unusually early the next evening, aim to keep a regular sleep schedule and only go to bed when you feel sleepy.
Short naps can be helpful if needed. A brief 20-30 minute nap in the early afternoon may help restore alertness without interfering with sleep later that night.
Don’t panic! Heatwaves pass, and a few disrupted nights are manageable for most healthy adults.
The bottom line
Our bodies need to cool down in order to sleep well.
During hot weather, the best approach is to support this natural process by keeping the bedroom cool, increasing airflow, choosing breathable bedding and maintaining healthy sleep habits.
Small changes can often make a noticeable difference, helping you stay comfortable and sleep more soundly even during a heatwave.
Today's phrazle is especially satisfying because it encourages creative thinking. Familiar expressions can appear surprisingly difficult when only a handful of letters are visible.
This is a very helpful guide for dealing with hot weather and improving sleep quality. The tips about airflow, breathable bedding, and maintaining healthy habits are simple but practical. Staying comfortable is important, just like how interactive platforms such as skribbl io create a more enjoyable experience through thoughtful design.