Heatwave: level three alert

A level three heatwave alert means that there will be heatwave temperatures in one or more regions, and you should take steps to stay cool. Find out how best to cope with the hot weather.

Heat can affect your health more than you might think. Prolonged exposure to hot temperatures can lead to worsening of heart problems, respiratory difficulties and serious health problems, and can also cause heatstroke, which is potentially fatal.

High temperatures can be dangerous, especially for:

  • the elderly 
  • the very young 
  • people with chronic or long-term medical conditions, such as a heart condition or breathing problems

During alert level three:

  • Listen to alerts on the radio and TV about keeping cool.
  • Avoid unnecessary travel. 
  • Visit or phone people who are vulnerable, such as older people living on their own or people with health conditions. 
  • Stay inside and in the coolest room in your home as much as possible, and splash yourself with cool water.
  • Keep rooms cool by using shade or reflective material outside the glass; if that's not possible, have light-coloured curtains and close them (metal blinds and dark curtains can make the room hotter).
  • Keep the windows closed while the room is cooler than it is outside, and, if it's safe, open the windows at night when the air is cooler than the room.


  • Enjoy the weather, but try to stay cool.
  • Avoid going outside between 11am and 3pm, as this is the hottest part of the day.
  • Spend time in the shade and avoid strenuous activity.
  • Help others: check up on neighbours, relatives and friends who may be less able to look after themselves (for example, if they have mobility problems). 
  • It is more important to keep yourself and others cool if you or they have a heart or respiratory condition. If symptoms become worse, seek medical advice.
  • Drink water or fruit juice regularly.
  • Avoid tea, coffee and alcohol, and if you do drink alcohol make sure you have water or other non-alcoholic drinks too. 

Heat exhaustion and heatstroke

Severe heat can cause heat exhaustion or heatstroke. Keeping yourself cool will reduce the risk of getting either. If you start to feel unwell, it's important to seek medical advice.

The symptoms of heat exhaustion include:

  • headaches
  • dizziness
  • nausea and vomiting
  • muscle weakness or cramps
  • pale skin
  • a high temperature

If this happens, move somewhere cool and drink plenty of water or fruit juice. If you can, take a lukewarm shower or sponge yourself down with cold water.

Heatstroke can develop if heat exhaustion is left untreated, but it can also occur suddenly and without warning.

Symptoms of heatstroke include:

  • headaches
  • nausea
  • intense thirst
  • sleepiness
  • hot, red and dry skin
  • a sudden rise in temperature
  • confusion
  • aggression
  • convulsions
  • loss of consciousness

If you suspect someone has heatstroke, call 999 immediately. Heatstroke can result in irreversible damage to your body, including the brain, or death.

Read more about heat exhaustion and heatstroke

Page last reviewed: 03/07/2014

Next review due: 02/07/2016


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