Heat health alerts have been upgraded to amber for much of the country as another UK heatwave looms.
As it upgraded the alert in advance of the country’s fourth heatwave of the year, the UK Health Security Agency (UKHSA) warned that the rising temperatures may increase health risks, particularly for vulnerable groups.
In recent days, temperatures have cooled, winds have picked up and a smattering of rain has fallen for many but the heat is expected to spike again in the south this week.
Parts of southern England will yet again meet their heatwave criteria on Wednesday, which could reach highs of 32C or 33C. Others will breach the threshold on Thursday.
The UKHSA said: “The existing yellow heat-health alert for the East Midlands, East of England, South East and London has been upgraded to amber and will be in place from 9am on Wednesday 29 July until 9am on Thursday 30 July.
“A yellow heat-health alert will remain in place for Yorkshire and the Humber, West Midlands and South West regions for the same time period.
“There is no alert in place for the North East and North West regions.”
Forecasters are expecting this week’s hot spell to be a “north-south split”, with clouds and outbreaks of rain continuing in Northern Ireland, Scotland and northern England.
But the peak will be “almost a blink and you miss it”, with temperatures widely cooling close to average by the weekend, said senior Met Office meteorologist Dan Stroud.
July was 3C above average across the UK, according to provisional Met Office data on the month so far.
This could put it among the hottest three or four months of July on record, said Mr Stroud.
The dry spell has contributed to low-water levels and North Wales and the Upper Severn became the first part of the UK to declare drought status on Thursday.
Emergency services are braced for further wildfires during the next heatwave.
At the height of the third heatwave, in mid-July, firefighters were battling 19 significant wildfires simultaneously in England and Wales.
Meanwhile, blazes have wrought destruction in mainland Europe this week, with 220,000 forced out of their homes in south-west France and 116,000 evacuated in Spain.
This comes as a Met Office meteorologist said UK heatwave thresholds will need to be adjusted to take into account the warming climate, which has seen temperature records repeatedly broken this year.
A National Fire Chiefs Council (NFCC) spokesperson said: “With the Met Office warning that a fourth heatwave could develop this week, bringing another period of very hot weather to parts of the UK, fire and rescue services remain on alert and are continuing to prepare for renewed wildfire risk.”
Battling nearly 20 wildfires at once demonstrates “the scale of the challenge posed by the prolonged hot, dry conditions”, they added.
“Most wildfires are preventable and we are asking everyone to play their part in helping to protect our communities, wildlife and natural spaces, while easing the pressure on firefighters who have already faced an exceptionally challenging summer.”
London Fire Brigade said it had attended more than 1,300 incidents, including grass fires and a person rescued from the Thames, over the weekend as the hot weather continued.
The service said it handled 2,729 emergency calls between Friday and Sunday, and firefighters attended 1,345 incidents across the capital, including a grass fire which destroyed 10 acres in Rainham, a hectare of grassland alight in Croydon, and blazes at flats, homes, sheds, a bakery and a storage unit.
The Brigade’s fire boat crews also rescued a person in the Thames near Battersea Pier.
The fire service is warning people not to use disposable barbecues in parks, to dispose of smoking materials responsibly, take litter home or put it in the bin, and use barbecues at home carefully away from anything such as sheds that could burn.
Fires, if they start, are likely to become exceptionally severe on Wednesday in pockets of the east, south, and south-east England, according to Met Office data used by Natural England and Natural Resources Wales.
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