“Could these European-style mega floods happen here? The honest answer is yes. There’s no physical reason why not."
Professor Hayley Fowler
Key points from the briefing
Extreme weather is not a future threat — it’s happening now. Europe has already seen “mega” floods and lethal heat. The UK is not exempt.
The UK is getting wetter in winter, and faster than models predicted. UK winter rainfall is up around 10% since 1980. That is 7.3 billion cubic metres of extra water each winter, or about 3 million Olympic swimming pools. The trend is worryingly around 25 years ahead of global model projections.
Flood risk is becoming a national-scale issue. By 2050, 8 million properties (1 in 4) in England could be at risk of flooding. An event of the scale of Storm Boris, which brought severe flooding to central Europe in 2024, would be a national crisis for the UK, with recovery taking years.
Extreme summer heat is escalating fast - and it kills. The UK hit 40°C for the first time on 19 July 2022. This was linked to around 3,000 excess deaths. The Met Office puts the chance of another 40°C day next year at around 4% - and rising.
Wildfire is now a UK risk, not just abroad. Hotter, drier summers are driving fires on heathland, forests and city edges — with fire services increasingly stretched beyond capacity during extreme heat.
Our infrastructure was built for a climate that no longer exists. Raised reservoirs, drainage, housing and transport were designed many years ago when extreme rainfall was rare and less severe. As rainfall intensifies, risks such as dam overtopping and cascading failures rise.
The UK is not adapting fast enough. The Climate Change Committee’s assessment is blunt: progress is too slow, with no sector outcome rated “good”, and major gaps in governance, responsibility and funding.
Adaptation is a “triple win” - and it pays back. Flood-absorbing parks, cooler greener cities, better insulation and resilient infrastructure protect people, cut bills, improve health and create skilled jobs, as in Copenhagen, which reinvented itself as a 'sponge city' after devastating floods.
This is the least extreme climate you will experience. Until we stop burning fossil fuels, extremes keep worsening - so we must cut emissions and build resilience now.
