London Daily

Focus on the big picture.
Saturday, Sep 12, 2026

Is the UK getting hotter, and what causes heatwaves?

Is the UK getting hotter, and what causes heatwaves?

After several days of warm weather, parts of the UK have experienced the hottest day of the year so far.

Temperatures hit 32.7 (91F) in south-east England on Friday, triggering an official heatwave, as hot air spread up from Spain, Portugal and north Africa.

Experts have said it's rare to see temperatures this high at this point in June.


Is the UK getting hotter?


Yes, Britain has been slowly getting warmer since the 19th Century. In the past three decades, the UK has become 0.9C warmer.

The 10 hottest years since 1884 have all happened since 2002. And none of the coldest years has been recorded this century.

In 2019, Cambridge saw the hottest temperature ever captured in the UK: 38.7C.


The summer of 2018 was the UK's second-warmest - shared with 1995 - since 1884. The hottest was in 1976.


When does hot weather become a heatwave?


A heatwave is a period of hot weather where temperatures are higher than is expected for the time of year.

In the UK, the Met Office declares a heatwave when it records at least three days in a row with maximum temperatures exceeding a set temperature.

That threshold varies by county.


Heatwaves usually happen in summer when high pressure develops over an area.

They can also bring so-called "tropical nights" - when night-time temperatures fail to drop below 20C.

That can make it hard to sleep at night and the body can suffer, as it fails to sufficiently cool down.

The Met Office says it's not clear whether heatwaves are becoming more frequent because of their sporadic nature.


Why are we seeing these changes?


Climate change is causing global temperatures to rise. Greenhouse gases, like carbon dioxide, released into Earth's atmosphere in large volumes are trapping the sun's heat, causing the planet to warm.

This has brought more extreme weather, including record-breaking high temperatures across the world.

Periods of intense heat do occur within natural weather patterns, but scientists say that globally they are becoming more frequent, more intense and are lasting longer as a result of global warming.

The UK is also seeing more dramatic rainfall as a result of climate change


In the UK, the Met Office has warned that summers like 2018 are 30 times more likely now than before the Industrial Revolution - the point when humans starting producing the emissions that are responsible for climate change.

A report on climate extremes in the UK found that recent years have seen both higher maximum temperatures and longer warm spells.

That trend is predicted to continue. It's possible that by 2100, the UK could see 40C days every 3 to 4 years.


Is hot weather dangerous?


Hot weather can be dangerous particularly for the vulnerable, including elderly people, children and people with underlying health conditions.

Spending too much time in high temperatures or in the sun, can cause health issues such as heat stroke and cardiovascular failure.


There are also indirect effects like poorer mental health and an increase in accidents such as car crashes and drownings.

In August 2003, 20,000 people died following a heatwave in Europe lasting 10 days, according to the Met Office.

The higher death rate starts to kick in once the thermometer passes 25C-26C.


How do you keep cool when it's hot?


Where possible, you should modify your routine and behaviour to adapt to the heat.

If you can, travel in the morning or evening when temperatures are lower.

Wear a high-factor sunscreen and a hat if you are going to spend time in the sun.


Newsletter

Related Articles

0:00
0:00
Close
UK Reviews Nationwide Emergency Alert Tests After Systems Meet Reliability Targets
UK Seeks Faster Rail Links Across Northern Industrial Corridors
British Business Bank Allocates £150 Million for High-Growth Companies in Northern England
BBC Warns Staff Strikes Are Possible Amid Pay Dispute and £500 Million Savings Drive
UK Backs Short Extension of UN Sudan Sanctions Regime
Prime Minister Andy Burnham Defends Early Prison Release Reforms and Growth Strategy
Reform UK Faces Scrutiny Over Alleged Effort to Circumvent Foreign Donation Rules
UK Analysts Warn Tax Rises or Spending Cuts May Be Needed to Preserve Fiscal Headroom
Jaguar Land Rover Plans Up to 4,000 Job Cuts in £1.7 Billion Cost-Saving Drive
UK Chancellor Warns of Difficult October Budget as Borrowing Costs Rise
UK Declares Israeli Occupation of West Bank Unlawful and Expands Sanctions
UK House of Commons Rejects Assisted Dying Bill for England and Wales
English Councils to Gain Power to Introduce Tourist Taxes by 2028
Kemi Badenoch Reshuffles Conservative Shadow Cabinet
Firefighters Make Progress Containing Major Wildfires in South Wales
John Lewis Partnership Reports £124 Million Loss
Study Says UK AI Data Centres Will Create Only a Quarter of Forecast Jobs
UK Government Considers Higher Industrial Water Prices Amid Supply Pressures
Andy Burnham Holds First Call With Donald Trump as UK Prime Minister
NHS Records Busiest Summer on Record as Heatwaves Drive Hospital Admissions
Home Secretary Orders Police Crackdown on Far-Right Anti-Migrant Vigilantes
UK Supreme Court Rules Northern Ireland Religious Education Curriculum Breaches Human Rights Standards
Markets Price in Four Bank of England Rate Rises by Next Summer
House of Commons Prepares Free Vote on Assisted Dying Bill
UK Government Bans Trade With Israeli Settlements in Occupied Territories
UK Economy Grows 0.4% in July as Artificial Intelligence Investment Supports Expansion
Andy Burnham Becomes UK Prime Minister After Keir Starmer Resigns
John Lewis Partnership Loss Widens to £124 Million
UK Government to Put White Working-Class Social Mobility at Centre of Equality Policy
McLaren Plans £450 Million Technology Investment Creating 1,000 UK Jobs
UK Chancellor Faces Calls for Wealth Taxes and Public Ownership in Autumn Budget
English Mayors to Gain Powers to Impose Uncapped Overnight Tourist Taxes
JPMorgan’s Jamie Dimon Warns UK Government Against Bank Windfall Taxes
UK Air Traffic Control Outage Cancels More Than 2,000 Flights
UK Imposes Trade Ban on Israeli Settlements in the West Bank
UK Borrowing Costs Surge as Middle East Tensions Push Long-Term Gilt Yields to Highest Since 1998
Buckingham Palace Says Prince Harry and Meghan Will Not Resume Official Royal Duties
UK Treasury Faces Calls to Scrap £100,000 Childcare Support Threshold
Trades Union Congress Urges Labour Government to Rewrite Migration Policy
Riot Police Deployed After Anti-Migrant Protests Turn Violent in Portsmouth
UK Considers Replacing Some Disability Cash Payments With Direct Services
JPMorgan’s Jamie Dimon Warns UK Chancellor Against Higher Banking Taxes
UK Announces New Sanctions Targeting Israeli Settlements in West Bank
Metropolitan Police Investigate Alleged Illegal Donations to Reform UK
UK Charges Wiltshire Man With Assisting Russian Intelligence
UK Orders Urgent Review After Air Traffic Failure Cancels More Than 2,000 Flights
Merz Rebukes AfD Expansion in Saxony-Anhalt
King Charles Confirms Prince Harry and Meghan Will Remain Private Citizens
Labour Selects Former Child Refugee for By-Election in Keir Starmer’s Former Seat
Foreign Private Equity Accelerates Takeovers of London-Listed Industrial Companies
×