UK weather: extreme heat in London, fires across the south and unexploded ammunition found

Droughts declared in eight regions of England

A bride poses for early-morning wedding portraits on Westminster Bridge, London, during the driest summer for 50 years. PA

More extreme heat and drought conditions are afflicting London and the southern half of the UK this weekend, while the northern half is set to be struck by thunderstorms and floods.

The UK Met Office forecast for London and the south-east of England has said it will remain sunny and dry into the afternoon, with conditions fractionally cooler on the coast. It forecast a maximum temperature of 35 °C in the region, some way off the UK record temperature set in July, when the mercury rocketed up to 40.2ºC at London's Heathrow Airport.

The highest predicted daytime temperature in London on Saturday is 35°C.

In response, the Met Office has issued an amber heat warning covering most of England and Wales for both Saturday and Sunday.

This means heat-related illnesses including sunburn and heat exhaustion are “likely” among the general population, and delays to public transport are “possible”.

Meanwhile, a lower-level yellow warning for thunderstorms is in place from noon on Sunday until 6am on Monday for most of Scotland and Northern Ireland.

This warning means there is a “small chance” of flooding in these nations and the potential for power cuts.

A day of wildfires in south England

It comes after an official drought was declared in eight areas of England on Friday by the National Drought Group, which comprises representatives from the UK government, water companies, the Environment Agency and others.

In Dorset, firefighters worked through the night to bring a wildfire at Studland under control, which was believed to have been sparked by a disposable barbecue, only to find an unexploded piece of ammunition believed to date to the Second World War on the scorched heathland.

County police said a bomb disposal unit would be attending and warned the public in the surrounding area they may hear a loud bang as they dispose of the device.

The Cornwall Fire and Rescue Service was battling a large wildfire in the town of Camborne. Authorities asked the public to stay away from the scene, as there was a danger of live electric wires falling.

Fire crews in Derbyshire were still tackling a huge blaze at 9pm on Friday night, with four fire engines at the scene in Creswell, Worksop.

Footage shared online showed flames filling the horizon and large plumes of smoke in the sky above a residential area.

Derbyshire Fire and Rescue Service also fought embankment blazes beside a railway in Matlock, and near Junction 26 of the M1.

The service said it was “planning for a busy weekend” of further fires. It echoed the pleas of fire services across the nation by asking people not to light fires in their gardens or use portable barbecues.

Ten fire engines and 70 firefighters were tackling a grass fire on Rammey Marsh in Enfield on Saturday.

"An area of grassland measuring around 900m by 600m remains alight," the service said, warning it is producing "a lot of smoke over the M25 between junctions 25 and 26".

About 35 firefighters tackled a blaze that destroyed two hectares of grassland at the Leyton Flats wildlife reserve in Waltham Forest, east London, on Friday.

Between August 1 and 10, Dorset and Wiltshire crews attend 180 wildfires compared to just 34 over the same period last year — an increase of 429 per cent.

The spokeswoman said operational staff had “never had a year like this one, it is just unprecedented”.

England water supplies 'safe'

England's drought could persist into the next year, the Environment Agency said.

John Curtin, executive director for local operations at the Environment Agency, said that after the driest summer in 50 years, it would take “weeks' worth of rain” to replenish water sources such as Kent's Bewl Reservoir.

The source of the UK's second longest river, the Thames, has retreated at least eight kilometres from where it should start.

The announcement could lead to more measures such as hosepipe bans. The Environment Agency has reassured the public that essential water supplies are safe.

Eight of 14 areas designated by the agency have now moved to “drought”. They are Devon and Cornwall, Solent and South Downs, Kent and South London, Herts and North London, East Anglia, Thames, Lincolnshire and Northamptonshire, and East Midlands.

Three water companies — Welsh Water, Southern Water, and South East Water — have imposed hosepipe bans, while Yorkshire Water has announced a ban will start on August 26 and Thames Water is planning one in the coming weeks.

UK drought - in pictures

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  The bed of the Woodhead reservoir as water levels sink in Glossop. There was a record-breaking heatwave in July, which was the driest July in records dating back to 1836 for south-east and central southern England. Getty Images

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  The parched grass lands of Greenwich Park in London. The country is facing its driest summer since 1976. EPA

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  Bewl Water Reservoir near Lamberhurst in Kent, which is currently measured at 67 per cent of its capacity as the dry weather continues. PA

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  A man walks along a dry bank of a tributary to the Dowry Reservoir close to Oldham. PA

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  Ardingly reservoir in West Sussex, owned and managed by South East Water, the water supplier for Kent and Sussex, which is restricting the use of hosepipes and sprinklers. PA

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  Low water levels at Holme Styes reservoir in Holmfirth, West Yorkshire. PA

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  A parched Parliament Square in London. EPA

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  Low water levels at Bewl Water reservoir in Lamberhurst. Getty Images

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  A groundsman at Boughton and Eastwell Cricket Club in Ashford, Kent, prepares the wickets for matches. PA