The guidance advises people stay out of the heat

Early indications from the Met Office hint at a warmer than average July and August this summer.

England's Chief Medical Officer Professor Sir Liam Donaldson set out measures people can take to protect their own health.

This second plan, updated from last year, highlights over 75s as high risk.

In 2003, about 27,000 people across Europe died directly because of the heat.

HOW TO COPE WITH A HEATWAVE Plan your day so you stay out of the heat Avoid going out 11am-3pm - the hottest part of the day If you go out, stay in shade, wear hat and light, loose clothes Carry water Take cool showers or baths - splash yourself with cold water, particularly face and back of your neck Eat as normal. Eat more cold food - salads and fruit

Within England, there were 2,000 excess deaths - 85% of which were amongst people aged 75 and over.

Health experts say it takes just two consecutive days of heatwave temperatures to have a significant effect on health.

And by 2080, experts believe events similar to those in 2003 will occur every year.

Heatwaves can lead to dehydration and heat exhaustion or heat stroke, which can then cause irreversible damage to various organs in the body and even lead to death.

Measures, such as staying out of the heat, drinking plenty of fluids and taking cool baths and showers could cut deaths, say experts.

Throughout the summer, NHS Direct and GPs will monitor the daily rate of heat related calls and consultations taking place.

Alerts

This monitoring system will trigger one of four levels of alert.

HEATWAVE ALERTS Level 1 - Awareness - general vigilance during summer Level 2 - Alert - triggered when heatwave temperatures are predicted in at least one region Level 3 - Heatwave - triggered when threshold temperatures have been reached in at least one region Level 4 - Emergency - where the heatwave is classed as severe and prolonged

Under level one, people would be issued with practical advice on how to keep cool.

Level four would be in used in an emergency where the severity or duration of the heatwave poses serious dangers to health.

A leaflet detailing the advice will be distributed to locations including GP surgeries, pharmacies and post offices.

Sir Liam said: "As the experience in 2003 demonstrated, it is particularly important that for those over 75, especially those who live alone or in residential homes, the necessary precautions are taken to avoid serious harm through heat exhaustion and heat stroke.

"Timely preventive measure can reduce excess deaths. The leaflet, designed to provide the public with common sense precautions, will help people to enjoy the weather whilst protecting themselves from the dangerous, and potentially fatal, effects of these temperatures."

Paul Cann, director of policy at Help the Aged, said: "To our shame, the UK has one of the highest rates of 'excess' winter deaths in the European Union and we do not want the same needless suffering to happen throughout our hotter summers too."