An unprecedented heat dome has enveloped much of western and central Europe, with daytime temperatures exceeding 40°C and nights offering little relief. Scientists describe the phenomenon as one of the most intense ever recorded for the month of June.
Nearly half of Europe’s major cities are experiencing severe thermal stress, with temperatures breaking records and triggering a cascade of problems for infrastructure, human health and the environment. Specifically:
France
France has been among the hardest hit, with temperatures reaching as high as 44°C. Two children died during the heatwave after becoming trapped in a vehicle that turned into a ‘death trap’.
Many people sought relief in rivers, lakes and the sea, leading to dozens of drowning fatalities. Schools were closed, outdoor events cancelled and restrictions imposed on public gatherings.
There were also power outages and major disruptions to the rail network. Eurostar cancelled train services between London and Paris ‘due to anticipated adverse weather conditions’.
The extreme heat caused the deaths of hundreds of thousands of poultry, while livestock production has also suffered, including a noticeable drop in milk output.
Spain
Temperatures exceeded 42°C and, according to scientific estimates, 212 premature deaths were recorded within just four days due to the extreme heat.
Scientists attribute these deaths to severe thermal stress caused by the prolonged heatwave. Tropical nights have further worsened conditions, particularly for the elderly and other vulnerable groups.
United Kingdom
Extreme temperatures forced the military to cancel guard-changing ceremonies and other events in London and Windsor in order to protect personnel.
Meteorologists reported a new all-time June temperature record of 36.7°C. Hospitals are facing increased caseloads, while transport systems and infrastructure are under strain.
Germany
Road surfaces have warped under extreme heat, while warnings have been issued about railway track deformation and transport delays. Authorities have also issued emergency guidance for the public.
Switzerland and Italy
In Switzerland, Basel recorded around 38°C, the highest June temperature in the country’s history.
In Italy, temperatures in many regions exceeded 40°C, prompting authorities to warn of increased risks for vulnerable groups and to introduce emergency measures in several cities.
Lack of infrastructure
Speaking to Politis, meteorologist Andreas Nicolaou highlighted the extensive protective measures being implemented by European governments, noting that public guidance is highly detailed. Authorities are even informing citizens about daily water intake, cooling methods, movement restrictions and warning symptoms requiring immediate action.
As he explains, societies in central and northern Europe are not accustomed to such extreme temperatures, nor do they have the necessary infrastructure. For example, only around 5% of homes in the UK have air conditioning, while in France the figure is estimated at about 7%.
15-20°C above normal
Former director of the Meteorological Service, Cleanthis Nicolaides, also commented to Politis on the phenomenon of extremely high temperatures in western, central and northern Europe, where readings are 15-20°C above normal.
He referred in particular to ‘tropical nights’, when temperatures do not fall below 20°C to 25°C. The human body’s inability to cool down at night leads to fatigue accumulation and significantly increases health risks, especially for vulnerable groups.
In addition to natural factors pushing temperatures to record levels, urban heat islands – resulting from extensive concrete development – further intensify heat in major cities.
Causes
According to Nicolaides, about a month ago a high-pressure system re-formed, raising air temperatures, initially affecting Portugal and the Iberian peninsula, with 44°C recorded in the desert zone of central Spain.
It then spread, and continues to affect, France, Germany and subsequently Poland and the Czech Republic.
Normal temperatures, he noted, should not exceed 15–20°C. The rapid shift is attributed to the movement of hot air masses from the Sahara towards Europe.
“Because this transfer occurs within an anticyclone, a high-pressure system, the air trapped within it heats up even more under pressure, producing the results we are now observing,” he explained.
At least eight nuclear power plants in France have shut down, he added, because river water used for cooling reactors has become too warm to use.
“This means electricity production has been reduced,” he noted.
More than 100 high-speed train services in France have also been cancelled due to problems in the power supply network.
European agenda
The intensity of the extreme heatwave is reshaping the EU agenda and placing climate change at the forefront of political priorities, Nicolaides said.
According to meteorological records dating back to the mid‑19th century, the current period ranks among the hottest ever recorded in central Europe.
Until recently, southern European countries were more frequently exposed to such extremes. Now, however, countries such as France, Germany, Austria, the Czech Republic, Slovakia and Belgium are facing increasingly severe impacts, likely strengthening EU adaptation policies.
Cyprus outlook
Meteorologist Andreas Nicolaou also raised the alarm over the effects of the heatwave, noting that the heat dome phenomenon, while weakening, is expected to affect Cyprus to a lesser extent.
Nicolaides added that the heat dome is moving towards Poland and gradually weakening, but part of its thermal energy is expected to reach the eastern Mediterranean.
He did not rule out temperatures in Cyprus reaching or exceeding 40°C from next week, stressing the need for heightened caution.
Water scarcity
Nicolaides also expressed strong concern about Cyprus’ water reserves, noting that dams are at around 43.8% capacity – a level he says is insufficient if one or two more dry hydrological years follow.
Significant volumes of water are expected to be lost through evaporation during the summer months, while current data does not point to a particularly wet winter ahead.
He also highlighted potential impacts on the primary sector, noting that limited irrigation water could significantly affect key crops such as potatoes, Cyprus’ second most important agricultural export after halloumi.
Cloud seeding
Nicolaides has also brought back into public discussion the use of cloud seeding technology to enhance rainfall, stressing that it is not a theoretical idea but one already applied in other countries.
As he puts it, authorities must seriously examine all available options rather than relying solely on hopes of a rainy winter.
He noted that desalination plants mainly cover drinking water needs rather than irrigation, while over-extraction of groundwater is steadily increasing pumping costs.
As he characteristically states, “hope alone is not enough; timely planning and prevention are required so that the country is prepared for the consequences of climate change.”
