Temperatures built to around 45C (113F) on Friday in many inland areas of Portugal, and are expected to peak at 47C (116.6F) in some places on Saturday.
The highest temperature recorded on Thursday, when the heat began to rise, was 45.2C (113.4F) near Abrantes, a town 93 miles north-east of the capital Lisbon, the country’s weather agency IPMA said.
Portugal’s highest recorded temperature is 47.4C (117.3F) in 2003.
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.
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.
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.
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).