Baby care in hot and humid weather

All ages · Care · Reviewed 18 June 2026 · All articles

Hot and humid weather creates specific challenges for babies, whose bodies are not yet efficient at regulating temperature. They heat up faster than adults, sweat less effectively, and cannot tell you when they are uncomfortable. During periods of intense heat or high humidity, parents need to be more alert than usual to a range of signs and to take some simple but important steps to keep their baby safe and comfortable.

This guide draws on guidance from the NHS and the World Health Organization (WHO) to cover feeding, skin care, sleep safety, clothing, and the warning signs that need prompt medical attention.

Keeping your baby cool

Babies have a limited ability to regulate their own body temperature. Their surface-area-to-body-weight ratio is higher than in older children and adults, which means they absorb heat from the environment more rapidly. Humidity compounds this, because sweat does not evaporate as efficiently in humid air, making cooling through perspiration less effective.

The ideal room temperature for a baby is between 16 and 20 degrees Celsius, according to NHS guidance. During hot weather, this range can be difficult to maintain without air conditioning. If you do not have air conditioning, keep windows on the shaded side of your home open during the day and open windows on the sunny side only after the temperature outside has dropped in the evening.

Fans can help move air around a room and reduce the feeling of heat, but avoid pointing a fan directly at your baby. Draping a damp muslin or towel in front of a fan can help cool the air slightly. Keep curtains and blinds closed on windows that receive direct sunlight, particularly between 10 am and 4 pm when the sun is strongest.

A cool (not cold) bath can help lower your baby's body temperature on a very hot day. This does not need to be a full bath routine: a gentle wash with cool water and a sponge is enough. Pat your baby dry and dress them in the lightest possible clothing afterwards.

If you are travelling in a car, remember that the temperature inside a parked car can rise to dangerous levels within minutes, even on a moderately warm day. Never leave a baby in a parked car, even briefly. Use sunshades on car windows and check frequently that your baby is not overheating during journeys.

Feeding in hot and humid conditions

Feeding needs may change in hot weather, and it is important to understand what your baby requires at different ages.

For babies who are exclusively breastfed, the NHS is clear: breast milk provides all the hydration a baby needs, even in hot weather. You do not need to give water to a breastfed baby under six months. Your baby may want to feed more frequently in the heat, and this is normal. More frequent nursing also helps your body produce milk suited to your baby's hydration needs, as breast milk composition shifts slightly in hot weather.

Formula-fed babies may be offered small amounts of cooled boiled water in very hot weather, according to NHS guidance. However, formula should still be the primary source of nutrition. Do not dilute formula to try to give extra water, as this reduces the nutritional content and can cause electrolyte imbalances.

Once your baby is over six months and has started solids, water can be offered alongside meals. Fruits and vegetables with high water content, such as watermelon, cucumber, and berries, are gentle sources of extra fluid for older babies.

Watch for signs of dehydration in hot weather: fewer wet nappies than usual, dark or strong-smelling urine, dry mouth, sunken eyes, or unusual lethargy. In a baby, dehydration can progress quickly, so contact your GP or seek urgent care if you notice these signs.

Skin care and heat rash

Baby skin is thinner and more sensitive than adult skin, and it reacts quickly to heat and humidity. Heat rash (sometimes called prickly heat or miliaria) is one of the most common skin issues in hot weather. It occurs when sweat ducts become blocked and sweat cannot reach the skin's surface. The result is tiny red spots or clear blisters, most often in skin folds, on the neck, around the nappy area, or where clothing fits closely.

Heat rash usually resolves on its own when the skin is kept cool and dry. The NHS recommends avoiding creams and lotions on heat rash, as these can block pores further. Loose, breathable clothing and good air circulation are the best treatments. A cool bath can provide relief.

Humid weather also increases the risk of fungal infections in skin folds, particularly in the nappy area and under the neck. Keep skin folds as dry as possible: pat them gently dry after bathing, change nappies frequently, and allow some nappy-free time each day to reduce moisture build-up.

For sun protection, the NHS advises keeping babies under six months out of direct sunlight altogether, as their skin is very sensitive. For older babies, use shade, protective clothing, and wide-brimmed hats as the first line of defence. A small amount of baby-specific sunscreen (SPF 30 or higher) can be applied to exposed areas for older babies when shade is not possible.

Mosquitoes and other insects are more prevalent in humid and wet seasons. Use mosquito nets over prams and cots where relevant. The NHS advises against using insect repellent on babies under two months, and for older babies, only products containing DEET at appropriate concentrations for children should be used, following the manufacturer's instructions.

Safe sleep in hot weather

Safe sleep guidance does not change in hot weather, but parents need to be particularly vigilant about overheating, which is a known risk factor for sudden infant death syndrome (SIDS). The NHS is clear that babies should never sleep with a duvet, pillow, or quilt, and this applies even more strongly in hot weather. A single, thin sheet is usually enough on a warm night.

Dress your baby in the minimum clothing needed for comfort. On very warm nights, a nappy alone may be sufficient. Remove hats and hoods before your baby sleeps: babies lose heat through their heads, and covering the head during sleep can cause dangerous overheating.

Check your baby regularly during the night in hot weather. Feel the back of the neck or the tummy (not the hands or feet, which are normally cooler) to assess whether your baby is comfortably warm. A baby who is sweating, flushed, or breathing faster than usual may be too hot.

Keep your baby's sleep space as cool as possible. If the room is above 25 degrees, a fan on low at a distance from the cot can help move air without creating a draught. Some parents find placing a bowl of ice in front of a fan provides gentle evaporative cooling for the room.

Frequently asked questions

Do I need to give my baby extra water in hot weather?

The NHS advises that breastfed babies do not need water even in hot weather, as breast milk provides all the hydration they need. Formula-fed babies may be offered small amounts of cooled boiled water in very hot weather. Once your baby is over six months and eating solids, they can have water with meals.

How can I tell if my baby is too hot?

Feel the back of your baby's neck or their tummy. If it feels hot and sweaty, your baby is too warm. Signs of overheating include flushed skin, rapid breathing, and unusual restlessness. Never rely on hands and feet as a guide to core temperature, as they are usually cooler than the rest of the body.

What is heat rash and how do I treat it?

Heat rash, also called prickly heat, appears as tiny red spots or blisters, usually in skin folds, on the neck, or where clothing sits tightly. The NHS recommends keeping the affected skin cool and dry. Loose, breathable clothing and moving your baby to a cooler environment usually resolve it within a few days.

Is it safe to use a fan or air conditioning near my baby?

Yes, fans and air conditioning can be used safely near babies. Avoid directing a fan or air-con unit directly onto your baby. Keep rooms cool but not cold: around 16 to 20 degrees Celsius is recommended for a baby's sleep environment by the NHS.

When should I seek medical help if I think my baby is overheated?

Seek urgent medical attention if your baby has a temperature above 38 degrees Celsius (36 degrees for babies under three months), is unusually drowsy or difficult to wake, has dry nappies suggesting dehydration, appears to be breathing very rapidly, or has a sunken fontanelle (the soft spot on the head). These signs need prompt medical assessment.

Track your baby's feeds, nappies, and temperature with Cubby. Spotting patterns in hot weather is easier when you have a log to look back on. Start free in the app.