The main risks posed by a heatwave are:
- dehydration (not having enough water)
- overheating, which can make symptoms worse for people who already have problems with their heart or breathing
- heat exhaustion
A heatwave can affect anyone, but the most vulnerable people in extreme heat are:
- older people, especially those over 75
- babies and young children
- people with a serious chronic condition, especially heart or breathing problems
- people with mobility problems – for example, people with Parkinson's disease or who have had a stroke
- people with serious mental health problems
- people on certain medications, including those that affect sweating and temperature control
- people who misuse alcohol or drugs
- people who are physically active – for example, labourers or those doing sports
The following advice applies to everybody when it comes to keeping cool and comfortable and reducing health risks:
- Shut windows and pull down the shades when it is hotter outside. If it's safe, open them for ventilation when it is cooler.
- Avoid the heat: stay out of the sun and don't go out between 11am and 3pm (the hottest part of the day) if you're vulnerable to the effects of heat.
- Keep rooms cool by using shades or reflective material outside the windows. If this isn't possible, use light-coloured curtains and keep them closed (metallic blinds and dark curtains can make the room hotter).
- Have cool baths or showers, and splash yourself with cool water.
- Drink cold drinks regularly, such as water and fruit juice. Avoid tea, coffee and alcohol.
- Stay tuned to the weather forecast on the radio or TV, or on the Met Office website.
- Plan ahead to make sure you have enough supplies, such as food, water and any medications you need.
- Identify the coolest room in the house so you know where to go to keep cool.
- Wear loose, cool clothing, and a hat if you go outdoors.
- Check up on friends, relatives and neighbours who may be less able to look after themselves.
Find out about the symptoms of dehydration.