Fire chiefs have issued a warning over outdoor fires and barbecues after a sevenfold increase in UK wildfires, as amber heat alerts were issued across England before what is expected to be a scorching weekend.

The UK has already experienced more than 500 wildfires this year, with incidents up 717% compared with the same period in 2024.

According to the National Fire Chiefs Council (NFCC), which represents the UK fire and rescue services, responders have been called to 564 blazes since 1 January, with more expected due to the heatwave engulfing the country.

Most wildfires in the UK are caused by human activity, sometimes accidentally and sometimes deliberately. The public have been urged not to use disposable barbecues in open countryside, parks and moorland areas, and not to discard cigarettes, matches or glass bottles, as they can ignite dry vegetation.

Phil Garrigan, the chair of the NFCC, said that fire and rescue services were already under “significant pressure” due to the high number of wildfires, and that “one small error” could lead to a blaze.

“We are deeply concerned about the escalating threat of wildfires this summer, which have the potential to become more frequent, intense and dangerous particularly in areas where communities border the countryside,” said Garrigan.

“We all need to play our part in protecting each other, our environment and our homes and businesses. We want everyone to enjoy the nice weather, we are just asking that they take extra care when out and about because it only takes one small error to lead to a significant wildfire.”

Amber heat alerts were issued in England on Thursday as the UK experienced its hottest day of the year so far, with 32.2C recorded at Kew in west London.

The UK Health Security Agency (UKHSA) said this week there could be “a rise in deaths” across all nine English regions due to the heatwave, with “those aged 65 and over or people with health conditions” particularly at risk.

The UKHSA said “significant impacts” were also likely across health and social care services in England. The alerts came into force at midday on Thursday and were expected to remain until 9am on Monday.

The Met Office said this week that the UK could exceed temperatures of 40C in the near future, and highs of 45C “may be possible” in the current climate.

This would smash the record of 40.3C recorded in Coningsby, Lincolnshire, in 2022. A report by the Office for National Statistics and the UKHSA found there were 3,000 more deaths in England and Wales that summer than would normally be expected.

In the first four months of this year there were more than double the number of rural blazes than in the months that preceded the 2022 heatwave, with the risk to people, wildlife and habitats described as “catastrophic”.

The dangerous 32C heat that may be endured by people in the south-east of England this Saturday will have been made 100 times more likely by the climate crisis, scientists have calculated.

Global heating, caused by the burning of fossil fuels, is making every heatwave more likely and more intense. The 32C day expected on Saturday would have been expected only once every 2,500 years without the climate crisis, the researchers said, and June heatwaves are now about 2-4C hotter than in the past.

The heatwave is the latest in a series of recent extreme weather events in the country. Between February and April, England had its driest period on record, with the north-west declaring a drought in May and Yorkshire entering one last week.

In order to avoid any negative effects from the weather, the UKHSA recommends people keep out of the sun between 11am and 3pm on the hottest days if possible, drink plenty of liquids and wear sunscreen and protective clothing when outside.

It also recommends looking out for people aged 65 and over, as they are especially affected by the heat.