Portugal and Spain are sweltering in a southern European heatwave that has produced near-record temperatures – with the hot conditions threatening to stick around for days to come.

The extreme weather, caused by an influx of hot air from Africa, is also carrying loads of dust from the Sahara Desert across some parts of the continent.

Portugal has issued red health alerts for extreme heat for more than half the country, with thermometers approaching 46C on Saturday.

Portugal’s highest recorded temperature is 47.4C (117.3F) in 2003.

The hot weather is also affecting Spain, where people crowded beaches at La Concha in San Sebastian Credit: AP

Emergency services have issued a red alert until Sunday, placing extra services such as medical staff and firefighters on standby.

In Portugal’s southern Alentejo province, streets remain largely deserted.

Some farmers chose to work during the night instead of in the heat of the day. Beaches around Lisbon, however, were packed.

Meanwhile, 400 firefighters and five water-dropping aircraft are battling a wildfire in southern Portugal’s Algarve region.

Portugal sees large wildfires every year, although unseasonably cool weather through the end of July has meant fewer blazes in 2018.

The government says only about 15% of the 10-year average area has been charred so far this year.

In neighbouring Spain, conditions are so hot and dry that the parched vegetation can spontaneously combust.

In the town of Nerva in the south of the country, a major emergency operation involving 200 firefighters and members of the military is taking place and residents have been evacuated from their homes, in a bid to tackle a wildfire which has already burnt through more than 120 acres.

Temperatures are being driven higher across the Iberian peninsula by a hot air mass moving north from Africa, which is also bringing dust from the Sahara Desert, meteorologists said. The dust gave the sky a dark yellow hue in some places.

A man takes his dogs to cool off in the sea at Larina beach near Muros in north western Spain Credit: AP

In Spain, heat warnings have been issued for 41 of the country’s 50 provinces as temperatures are expected to reach up to 44C (111.2F).

Spain’s highest recorded temperature is 46.9C (116.42F) in Cordoba, a southern city, in July 2017.

The World Meteorological Organisation says continental Europe’s record is 48C (118.4F) in Greece in 1977.

In northern Europe, Sweden is still under threat from wildfires, which in recent weeks have extended into the Arctic Circle.

Sweden’s Civil Contingencies Agency warned of “a high risk” for wildfires in central and southern Sweden this weekend because of the continuing dry weather and strong winds.

A man cools off in a public fountain at the Retiro park in Madrid, Spain Credit: AP

In Moscow, as temperatures rose to close to 30C (86F), city authorities announced they are opening hundreds of “cool rooms” where residents can rest amid air conditioning, with water dispensers and medical attendants.

Although that temperature is far below the blazing heat hitting southern Europe, it is well above the Russian capital’s average August maximum of 23C (73F).