European heatwave leaves Spain, Portugal, Italy and Greece in sweltering 40C heat

Major heatwaves across southern Europe have left Spain, Portugal, Italy, and Greece in sweltering conditions of more than 40C (104F).

Two-thirds of Portugal was on high alert for extreme heat and risk of wildfires on Sunday, with temperatures in Lisbon expected to exceed 42C (107F).

In parts of southern Spain, temperatures are well above average, with 42C also expected in Seville and other cities.

The country's meteorological service says June is likely to be the hottest Spain has experienced since records began.

In several Italian regions, including Lazio, Tuscany, Calabria, Puglia, and Umbria, outdoor work was banned during peak hours of sun on Sunday, with trade unions pushing for the measures to be extended and rolled out nationwide.

Twenty-one out of 27 cities were under the highest possible heat alert, including Rome, Milan, and Naples.

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Greece has already been plagued by wildfires this summer, with one breaking out south of Athens on Thursday, and several on the island of Chios last Sunday.

Near Athens, authorities deployed 130 firefighters, 12 helicopters, and 12 planes, with 40 people evacuated from the highest-risk areas.

A woman was arrested on suspicion of unintentional arson after wildfires spread across brush and pastureland for three days on Chios.

Scientists link increasing frequencies of extreme weather events such as heatwaves, wildfires, and storms to climate change.

In France and Germany, at least three people died amid stormy conditions.

A ridge of high pressure above central and western Europe is driving the scorching conditions, says Sky News meteorologist Chris England.

Hotter-than-normal sea temperatures, dry land, and surface winds are also partly to blame, he added.

UK heatwave also likely

The UK is halfway through a four-day amber heat health alert, with temperatures expected to peak in the mid-30s (86F) on Tuesday.

Heat health alerts are not public weather warnings - but are instead designed to prepare health and social care bodies for the potential impact on their infrastructure and vulnerable groups.

Heatwave thresholds are likely to be met on Monday and Tuesday, which vary between 28C (82F) in the south of England and 25C (77F) across the rest of the country.