'We are all at risk': Dire warning from ambulance chief as Britain faces 40C heatwave

Temperatures are forecast to hit highs of 40°C in the south of England as a so-called "heat dome" weather phenomenon dominates Europe across Wednesday and Thursday.

The Met Office had initially enforced amber alerts but then replaced them with red "extreme heat" warnings.

Craig Harman, chief operating officer of London Ambulance Service NHS Trust, told LBC that his colleagues are expecting a 50% increase in demand this week as he issued stern advice for staying out of danger in extreme heat.

He also urged people to 'stay away from the water' and stay away from swimming in unsupervised bodies of water such as rivers and lakes.

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The trust has already received around 7,000 calls per day across the weekend and into Monday, and a 16% rise in calls for patients fainting, before the extreme heat is due on Wednesday and Thursday.

The London Ambulance Service usually takes around 5,500 calls on a typical day.

Mr Harman told LBC: "The Met Office has issued an extreme red weather warning which means in some way we are all at risk.

"It's likely to end up being our busiest week on record with 50% more demand than we would typically see.

"We are encouraging everybody to think about what they are doing to keep themselves out of the sun, particularly during the busy bits of the day.

"Even if you don't feel thirsty, we would ask people to really consider keeping themselves hydrated.

"Of course there are groups of people that will suffer more in the heat like elderly and vulnerable people and those with underlying medical conditions, particularly patients with cardiac conditions and respiratory illness.

"We'd ask people to also look out for each other and if you do have an underlying medical condition, make sure that you have the stocks of all your medicines."

The Met Office is predicting temperatures of 40C in London on Wednesday and 39C on Thursday, before it drops back down to 29C on Friday.

The extreme heat, which has been very rare in the UK until now, will be accompanied by high humidity, and very warm and humid nights which will make it hard for people to recover overnight, the Met Office said.

As a result, the public is being advised to wear loose clothes and eat cucumbers to help combat the conditions.

At least 15 people died in open water during the most recent heatwave over the May bank holiday, and Mr Harman is pleading with Brits to think twice before entering the water to cool off this week.

He said: "My message is to simply to stay away from the water. Whilst it will look really tempting, it could be dangerous.

"The Coast Guard have got really good advice for people, but we would ask people to stay away from open water and definitely not swim despite how tempting it may be.

"The red warning is a real sign for people to think about how they're going to behave in the coming days."

It is the first red warning for heat since July 2022 when the UK saw its highest temperature on record of 40.3°C in Coninsby, Lincolnshire.

Giving his advice to the public on how best to use the NHS across the week, Mr Harman said: "We are really asking people to use their ambulance service wisely and only calling us in a genuine emergency.

"We are also encouraging people to use other bits of the NHS like NHS 111 online and indeed your pharmacy.

"There, you will likely get care quicker and that is appropriate for your needs."

He added: "We have well-rehearsed plans in place and will be deploying additional resources so there'll be more ambulances in London to help deal with that demand.

"All of our managers and clinicians will be patient-facing this week to help out.

"We'll be focusing on like the highest priority patients and looking to support patients in other ways to make sure that we protect our response to the sickest patients."