UK heatwave triggers air pollution alert as people flock to beaches.

Teenager and woman drown in separate incidents as sweltering heat forces Royal Ascot to consider relaxing dress code

<!–[if IE 9]><![endif]–>Sunbathers pack the beach at Barry Island, south Wales, on Monday.




Sunbathers pack the beach at Barry Island, south Wales, on Monday.
Photograph: Ben Birchall/PA

UK heatwave triggers air pollution alert as people flock to beaches

Teenager and woman drown in separate incidents as sweltering heat forces Royal Ascot to consider relaxing dress code

The heatwave that has brought the longest spell of high June temperatures for two decades has also triggered an air pollution alert in London, with southerly winds due to bring toxic air to large parts of England and Wales on Wednesday.

Thousands of people flocked to the coast to enjoy the sunshine and temperatures of more than 30C (86F) on Tuesday, but experts warned that poor air quality would reach dangerous levels on Wednesday as temperatures are forecast to top 33C in the capital.

The London mayor, Sadiq Khan, issued the emergency alerts, which are displayed on thousands of bus stops, road signs and on the underground.

A spokesperson said that due to “continued warm and sunny weather conditions, high levels of pollution are forecast tomorrow, particularly near busy roads. As a result of this the mayor has triggered a London-wide air quality alert this afternoon on the transport system to ensure Londoners are fully aware and able to take any extra precautions needed.”

Experts warn that anyone with lung or heart problems should avoid or reduce strenuous physical exertion, particularly outdoors. Older people or those with asthma should take particular care.

As the hot weather has continued, crowds sought refuge at beaches and rivers. But the public were warned to take extra care after two people drowned.

The first, a teenager, died on Monday evening while swimming at Greenbooth reservoir in Rochdale, despite the efforts of his friends who dived repeatedly to try to bring him back to the surface.

At West Wittering beach in West Sussex, the emergency services were called on Monday afternoon when a woman got into distress while swimming. She was dead when she was pulled from the water.

The hot spell is due to break on Thursday, with thundery downpours in many parts of the south, and fresher weather spreading across the country on Friday.

<!–[if IE 9]><![endif]–>The Glastonbury festival site


The Glastonbury festival site. Organisers and punters are anxiously watching the weather forecasts for signs of rain. Photograph: Ben Birchall/PA

However, experts say before that happens pollution levels are likely to peak late on Wednesday afternoon.

Simon Birkett, from the Clean Air in London campaign, said Bournemouth had already breached the EU’s threshold at which instances of ozone pollution must be reported to the European commission, and warned that large parts of England and Wales would be affected on Wednesday.

“This is a very serious episode, which unfortunately combines high levels of ozone with high levels of particulates, so it is very important that people keep an eye on these alerts and follow the health guidelines.”

Air quality researchers at King’s College London issued a statement on Tuesday warning of high pollution levels as southerly winds are expected to bring in toxic air from the continent on Wednesday. The environment department’s air quality analysis shows moderate or high pollution is likely to affect large parts of England and Wales on Wednesday.

Researchers said the toxic air was caused by high ozone levels brought up from industrial parts of France by a southerly wind. They also warned that particulate levels – from cars and lorries and other fuel burning – are expected to be “moderate, with high again a strong possibility”.

The government has come under growing pressure about the UK’s air quality. It has had a string of humiliating defeats in the courts over its failure to clean up the nation’s air – the latest of which was last week, when a high court judge said the continued delays were “a significant threat to public health”.

The subsequent report was deemed to have “major flaws” by experts, and environmental lawyers are now taking ministers back before judges.

Khan said he was implementing a “hard-hitting programme” to tackle air quality in the capital, but added: “The government must urgently get a grip on this health emergency and introduce a new Clean Air Act that takes air pollution seriously, plus a national diesel scrappage fund and reforms to vehicle excise duty.

“But given that much of the toxic pollution today in London is being blown over from the continent, we must continue to work closely with our neighbours to reduce emissions across Europe, even after Brexit.”

The heat was also having an impact on sporting events. At Royal Ascot organisers were forced to consider allowing men to remove their suit jackets and top hats at the race meeting. “It’s being considered. We’re waiting for confirmation. It’s never happened before,” a spokeswoman said.

In the royal enclosure men are required to wear black or grey morning dress with a waistcoat and tie – but not a cravat – and a black or grey top hat. For women a range of arcane rules ban very short skirts, spaghetti straps and bare stomachs.

“If it is becoming uncomfortable, we would let people take their jacket off and relax a little bit,” a spokesman told the Times. “A course-wide announcement would be made and it will be up to individuals to make their own decisions.”

Frances O’Grady, the general secretary of the TUC, called on employers to relax workplace dress codes. “Obviously shorts and flip-flops won’t be the right attire for all workers, but no one should be made to suffer unnecessarily in the heat for the sake of appearances,” she said.

Glastonbury organisers and festivalgoers were keeping a particularly anxious eye on the forecasts, especially the prediction that the scorching weather could break on Wednesday night and early Thursday – hours after the gates open, and in time to create the traditional quagmire before the main stage acts start on Friday – with bouts of “torrential rain, frequent lightning and a chance of hail”.

The long run of very hot days and sweltering nights is unusual so early in the summer, but this week’s temperatures are unlikely to topple the hottest June ever – in 1976, when it was 35.6C.