A heatwave starting this weekend and persisting into the coming week has been forecast by the Greek weather service, with temperatures as high as 40C and low wind speeds in several parts of the country.

Experts warned that discomfort levels may be high, especially in urban centres, while Greek local authorities have prepared for the summer's first heatwave by making public air-conditioned areas available for those most vulnerable to the high temperatures.

They also advise the public, both healthy and more vulnerable individuals, to avoid prolonged exposure to the sun and high temperatures as this can lead to serious health problems.

Talking to the ANA-MPA, Athens Medical School pathology professor Anastasios Spantideas said that especial care must be given to the very young and very old, since in both cases the body's heat-regulating mechanisms are either too immature or less able to adjust to temperature extremes.

Others more vulnerable to high temperatures are pregnant women, especially in the final stages of pregnancy when there is more stress on the heart and respiratory system, persons with thyroid disorders, especially hyperthyroidism, as well as people with respiratory and cardiovascular complaints.

Doctors warned that even healthy people can succumb to heat unless they take certain precautions, such as avoiding strenuous exercise or manual labour, ensuring that they are in properly air-conditioned or shady environments, that they are lightly dressed in light-coloured clothing and wear a hat outdoors.

Spantideas also advised people to drink lots of fluids, such as water or natural fruit juices, prefer light and easily digestible foods, have small, frequent meals that include vegetables and fruits. He warned against excessive intake of salt and also against consumption of alcohol.

He also noted that taking a cool shower was another useful tool in dealing with excessive heat.

According to the weather service, temperatures will remain in the high 30s or even reach 40 on Monday and Tuesday and will gradually start to drop from Wednesday, initially only in western parts of the country, when wind speeds are forecast to rise.