Five departments in southeastern France have been placed under an amber heatwave warning by M茅t茅o-France, with temperatures expected to near 40掳C in some areas.

Ard猫che, Alpes-Maritimes and Var have joined Dr么me and Alpes-de-Haute-Provence, which have been on amber alert since Wednesday, August 11.

Temperatures of between 36 and 39掳C are predicted from today (August 13) until Sunday, and are even expected to reach 40掳C in Provence.

Minimum temperatures will also be four or five degrees higher than the seasonal average, and perhaps even hotter on the C么te d鈥橝zur, at 23-26掳C.

At 05:00 today, most of the areas under amber alert were experiencing temperatures of 20-22掳C, while in locations along the C么te d鈥橝zur, including Nice and Fr茅jus, it was already 26掳C.

People in amber alert departments - especially the elderly, babies, young children, pregnant women and the unwell - are advised to be 鈥渧ery vigilant鈥� to the effects of the heat, taking extra care to stay hydrated and to keep out of the sun.

You can seek advice on how to protect yourself from the heat by calling France鈥檚 Canicule info service between 09:00 and 19:00, Monday to Saturday, on 0800 06 66 66.

There are also 13 southeastern departments - Pyr茅n茅es-Orientales, Aude, H茅rault, Gard, Bouches-du-Rh么ne, Vaucluse, Loz猫re, Haute-Loire, Rh么ne, Is猫re, Hautes-Alpes and the whole of Corsica - that have been placed under a yellow heatwave alert.

In these places, maximum temperatures are expected to rise to 33-37掳C, peaking at 37-39掳C in Gard, Vaucluse and Bouches-du-Rh么ne.

When does hot weather become a heatwave?

In France, a heatwave (canicule) is defined as a period of very hot weather which lasts for at least three consecutive days.

For the conditions to reach canicule levels, the temperature must remain high at night as well as during the day.

The temperature threshold for a heatwave depends on the region of France, but as an example, the city of Toulouse might be classed as in a canicule if maximum temperatures exceeded 36掳C for three days in a row, failing to drop below 21掳C at night.

M茅t茅o-France's heatwave alerts follow a traffic light system of yellow, amber and red, with red triggering the introduction of special measures from the government to try to manage the situation.

While weather conditions remain on an amber alert, local authorities will know to pay extra attention to care-home residents, homeless people and other vulnerable groups, to help them combat the debilitating effects of the heat.

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