Norfolk folk hoping to bask in glorious sunshine should be wary of "serious" health implications, experts say.

Forecasters expect temperatures in the county to hit 33C on Friday, June 17, and stay at high levels until midnight on Saturday, June 18, with a level three heatwave warning now in place for the region.

The county has seen its warning level increase after the UK Health Security Agency (UKHSA) originally issued a level two warning.

Level three is an amber warning and means older people, young children, and babies, as well as those with underlying health conditions, should take care.

Under the warning, the UKHSA advises people to close curtains in rooms that face the sun, drink plenty of fluid, avoid excess alcohol, and dress appropriately for the weather.

Experts have also been warning people of the dangers surrounding the hot weather.

Dr Louise Smith, Norfolk's director of public health, said: “A lot of people are really looking forward to the sunshine and warm weather, and there’s no reason not to enjoy yourself provided you take some simple steps.

"Keep out of the sun in the middle of the day, apply sunscreen and wear appropriate clothing – including a hat – and you can stay safe.

"It’s also vital to stay cool, drink plenty of water and avoid excessive alcohol or caffeine: these are simple things we all know we can do and if we make time to do them, we can safely and happily enjoy the summer weather."

Dr Radhika Khosla of the University of Oxford, said: “The health implications of rising temperatures in the UK are serious.

“Important physiological changes occur in response to high temperatures including changes in our circulatory, nervous and respiratory systems.

“When these adaptive measures are not enough, the risk of cardiopulmonary and cardiovascular problems increases among older adults, young children, people with chronic conditions, athletes, and outdoor workers."

Forecasters say warm air from Spain and Portugal, where daytime temperatures have exceeded 40C, is driving the mercury higher further north.

Britain's highest recorded June UK temperature was 35.6C at Southampton Mayflower Park in June 1976.