Keeping Your Baby Safe From Summer Heat
Heat affects babies faster than adults, and the two biggest summer risks are easy to miss: giving a young infant water, and the temperature inside a parked car. A baby's body heats up 3 to 5 times faster than yours. This guide covers why infants under 6 months should not be given extra water, how to recognize overheating and dehydration, and the hard rule that keeps children safe in vehicles.
No extra water before 6 months
In the first 6 months, babies do not need water or juice in addition to breast milk or formula, even on hot days, unless a pediatrician advises otherwise. Breast milk and formula provide all the fluid a young infant needs. Giving extra water can disrupt the balance of sodium and other electrolytes and, in serious cases, lead to seizures.
Around 6 months, you can introduce small amounts of water. Babies that age only need about 4 to 8 ounces per day until their first birthday. To keep a young baby hydrated in heat, offer breast milk or formula more often rather than water.
Know the signs of overheating and dehydration
A baby cannot tell you they are too hot or losing fluids, so watch for physical signs. Catching dehydration early lets you respond before it becomes serious.
- Fewer than six wet diapers in a day for an infant
- Few or no tears when crying
- A dry, parched mouth
- A sunken soft spot on the head
- Sunken eyes, unusual sleepiness, or hard-to-wake lethargy (signs of more severe dehydration)
Never leave a child in a car
Heatstroke is the leading cause of non-crash, vehicle-related deaths in children under age 15. The inside of a car heats up fast: in just 10 minutes, the temperature can climb 20 degrees Fahrenheit. Heatstroke can occur when it is as mild as 57 degrees outside.
Cracking a window, parking in the shade, or running the air conditioner before you leave does little to change how hot the interior gets. A child's organs begin to shut down at a body temperature of 104 degrees, and 107 degrees can be fatal. Never leave a baby or toddler alone in a vehicle for any length of time.
Build habits that prevent a forgotten child
Most hot-car deaths are not careless parents; they are routine changes, exhaustion, and a quiet sleeping child. Build checks into your routine so the back seat is never an afterthought.
Put your phone, bag, or work badge in the back seat next to the car seat so you have to open the back door every time you park. Ask your childcare provider to call you if your child does not arrive as expected. If you ever see a child alone in a hot car and are concerned, call 911 immediately.
Common questions
- Can I give my baby water in hot weather?
- Babies under 6 months should not be given water or juice in addition to breast milk or formula unless a pediatrician advises it. Extra water can upset their electrolyte balance. To keep a young baby hydrated in heat, offer breast milk or formula more often.
- How much water can a baby have after 6 months?
- After about 6 months, babies can have small amounts of water, roughly 4 to 8 ounces per day, until their first birthday. Breast milk or formula should still be their main source of fluids.
- What are the signs of dehydration in a baby?
- Watch for fewer than six wet diapers a day, few or no tears when crying, a dry mouth, and a sunken soft spot. Sunken eyes, extreme sleepiness, or being hard to wake are signs of more severe dehydration that need medical attention.
- How fast does a parked car heat up?
- A car can heat up by 20 degrees Fahrenheit in just 10 minutes. Heatstroke can happen even when it is as mild as 57 degrees outside, and cracking a window does little to change the interior temperature.
- Why do children overheat faster than adults in cars?
- A child's body heats up 3 to 5 times faster than an adult's. That is why a car that feels warm to you can become deadly for a baby quickly, and why a child should never be left in a vehicle for any length of time.
- At what body temperature is heatstroke dangerous for a child?
- A child's organs begin to shut down when body temperature reaches 104 degrees Fahrenheit, and 107 degrees can be fatal. Vehicular heatstroke is the leading cause of non-crash vehicle-related deaths in children under 15.
- What should I do if I see a child alone in a hot car?
- Call 911 immediately. A car interior can reach dangerous temperatures within minutes, and a young child can suffer heatstroke quickly. Do not wait to see whether a caregiver returns.
Sources & further reading
Track every stage in one calm app.
ParentFlow is a free baby tracker that logs feeds, sleep, diapers, pumping and growth in one tap, with your daily summary, trends, and reminders based on your own logs. Free for everyday tracking on iPhone, Android, and the web.
App Store Google Play Open Web AppThis guide reflects current AAP, CDC, and other public-health guidance and is for educational purposes only. It does not constitute medical advice. ParentFlow is a wellness companion — not a substitute for your pediatrician. For any medical concern, contact your healthcare provider.