Weather: Heatwave Health Alert As Mercury Rises

Britain saw the hottest day of the year so far amid health warnings over the country's first heatwave for seven years.

After five consecutive days basking in 30C-plus temperatures, forecasters said Britain was in the midst of its first prolonged heatwave since 2006.

The Met Office responded by issuing a "level three heat health watch" for London and the South East and advised "alertness and readiness" for those in the North West and North East.

Level three warnings are only one notch below the most serious alerts and are put out when high temperatures place the very young, the very old and those with chronic diseases at risk.

Temperatures reached 32.2C (90F) at Hampton in Surrey on Wednesday afternoon, making it the warmest weather since Saturday when a high of 31.4C (88.5F) was recorded at Heathrow Airport.

Referring to the level three heat-health warning for London and the South East, Sky News weather presenter Isobel Lang said: "The temperature threshold for the region is for daytime highs of 31 or 32C (90F) and night minima of 16 to 18C (64F) over two days and the intervening night."

The alert comes after a series of tragic accidents in which people have died trying to cool off.

Emergency services have reiterated a warning of the dangers of swimming in open water after the bodies of two men were recovered from the water at a beauty spot in Norfolk where swimming is banned. A teenage boy and man in his 40s were found in separate lakes at the Bawsey Pits.

There have been four water-related deaths in Wales over the last week. In the latest accident a man in his twenties was reported dead on Wednesday morning after being pulled from the River Ceiriog at Pont-y-Blew, near Wrexham, the previous evening.

In the Brecon Beacons, a 24-year-old man died while swimming at the Cantref Reservoir and a 52-year-old man did not return from his swim in Pontsticill Reservoir in Merthyr Tydfil.

Only days earlier the body of 14-year-old Hollie McClymont from Glasgow was found in the sea near Fontygary in the Vale of Glamorgan. She was last seen in difficulty in the waters near Barry Island.

Two TA soldiers died of suspected heat exhaustion during an SAS assessment in the Beacons on Saturday.

Doctors at the Abertawe Bro Morgannwg University (ABMU) health board, which covers Swansea, say they have been inundated with people suffering with sunstroke and sunburn.

Other cases have included toes being amputated due to gardening accidents as well as a rise in those hurt in falls.

Emergency departments have become so busy that people not seeking urgent medical attention are being urged to instead contact their GP or pharmacist to avoid long waits.

ABMU emergency medicine consultant Andy MacNab said: "We are very busy, and we would urge people to take great care during this hot weather. They need to stay cool, avoid sun burn and keep well hydrated.

"If they are using a lawnmower or strimmer, then they need to have sturdy footwear and not cut grass in flip-flops.

"If they are taking part in sports, then they should ensure they are using all the necessary safety gear for their activity, like helmets, for example."

Firefighters in London have dealt with twice as many grass fires this summer compared with last year, with 1,010 so far.

Motorists have been advised to prepare for summer "getaway" traffic as schools start to break up at the end of this week - including basic checks on coolant levels, tyre pressures and cooling fans.

Traffic is expected to peak on the weekend of July 26-28, with the busiest routes expected to be in the South West as people head for beaches.

Some relief from the heat is in sight, with cooler northeasterly winds set to bring cloudier skies across eastern Scotland and eastern and southeast England from Thursday.