In fact, tropical nights – when temperatures don’t dip below 20C – have become an increasingly common, sweaty fixture in Europe since the 1980s, and it’s disrupting both lives and holidays in unexpected ways.
Last year, southern European summer destinations – including the sun-drenched shores of southern Italy, Croatia, Turkey and Greece – sweltered through a record-breaking 23 tropical nights, according to new data.
That’s nearly three times the average of just eight, and far above the previous record of 16 in 2012, the EU’s Copernicus Climate Change Service said.
Tropical nights mean a sleepless, sticky time in bed, when sweaty sheets cling to skin and opening windows brings no respite.
Dann Mitchell from the UK’s Met Office said nighttime temperatures are “really important for our health” because it’s the part of each day when we recover. And if it can’t do that, it brings a “whole host of issues”, he warned.
These sweltering figures came in what was the hottest year ever in Europe. But they aren’t a one-off. Climate change is making the atmosphere warmer, bringing ‘heat stress’ in the day as well as at night.
Last year there were also 66 days of ‘strong heat stress’ across southern Europe – when daily temperatures reach a ‘feels-like’ temperature of 32°C or higher – far surpassing the average of 29 days.
The price of sleepless nights
Soaring daytime highs paired with sultry nights are pushing the limits of human comfort – and health.
Madeleine Thomson, Head of Climate Impacts & Adaptation at health research foundation Wellcome, said: “Europe is heating up, and we’re not prepared for the toll this will take on our health.”
“Deaths from heat stress are the most visible impact. But extreme heat doesn’t just kill – it also increases the risk of heart disease, pregnancy complications, and poor mental health.”
In Britain’s scorching summer of 2022, an extra 2,800 people aged over 65 are estimated to have died from heat-related reasons.
Children are especially vulnerable because they are small and so warm up faster. Pregnant women, whose bodies already struggle with temperature regulation, are also at risk.
While air conditioning “helps us to survive”, it is energy intensive, increasingly unaffordable, and can lead to power blackouts when the system is overloaded, said Ilan Kelman, professor of disasters and health from Reading University.
Earth, wine and fire
But it’s not just tourists who are feeling the heat.
“The economic consequences are profound,” said Dr Hannah Cloke, a hydrologist at Reading University, including for farmers grappling with withering crops and crusty soils.
Wine harvests were down last year, variously described by the industry as “dismal” and “horrible”.
Meanwhile while olive trees were parched by heat and drought, pavements in Italy melted, and a fire near Athens burned almost 11,000 hectares (110 km2).
Holiday company Intrepid Travel said it has “definitely seen an increase in the severity and frequency of extreme weather events impacting our trips in Europe”.
It is adapting to this “new reality” by scrapping hiking holidays in Turkey in July and August and running new summer trips to Scandinavia – with bookings from Brits up 40% last year.
Google told Sky News it had detected a new, rapidly growing trend for searches like “summer holiday in Europe not too hot” and “what summer holiday destinations do not have risk of wildfires in July”.
A hotter future
The record-breaking summer of 2024 may have been extreme, but it’s part of a long term shift, said Copernicus.
Europe is the fastest-warming continent, warming twice as fast as the global average – partly due to its overlap with the Arctic.
The weather still varies wildly, so scientists can’t predict the exact number of tropical nights or heat waves this year, but they are confident in the trend.
Madeleine Thomson, head of climate impacts at Wellcome, said: “We urgently need to cut emissions and adapt our cities. Simple changes, like adding green spaces and waterways, can help cool urban areas and protect public health.”
