Wildfire warning as Britain enjoys best summer in years

Fire chiefs say nature reserves are under threat while forecasters expect 32C in the South-east

Grass fires that have damaged nature reserves and rural land across Britain this week will become more frequent as the heatwave continues, firefighters warned last night.

The combination of scorching temperatures and the start of the school holidays on Friday will make this weekend a “peak” for brush fires, many of which are started deliberately by children. The hot, dry weather has turned large areas of countryside into a tinder box, with 21 grass fires a day recorded in the London area this month.

The temperature is forecast to reach 32C (89.6F) in parts of South-east England today, making it the hottest day since last August. A near-high for 2013 of 31.2C was recorded at Kew Gardens in Surrey yesterday.

“This weekend could be a bit of a peak for grass fires, as the holidays start and the continuing dry weather increases the risks of fires spreading rapidly,” said John Ballard, a spokesman for Cumbria Fire and Rescue Service. “We would urge parents to keep an eye on their kids.”

Chobham Common in Surrey, the largest nature reserve in the South-east, caught fire on Monday night and destroyed five acres of ancient lowland heath that is home to hundreds of species, such as the rare Dartford warbler.

Emergency crews also tackled three separate blazes on common land around nearby Godalming, as well as in Carlisle and elsewhere in Cumbria, and another in Bolton.

All have been blamed on arson and the concern is that, with high temperatures and low rainfall forecast to continue for at least another month, unsupervised children will inflict increasingly severe damage on the countryside by setting fires that accelerate rapidly.

Alan Grant, a station manager with Surrey Fire and Rescue Service, which put out the fire on Chobham Common, said: “It looks like this was suspicious activity by juveniles playing with matches and we are working with Surrey Police on this.

“We have all the ingredients for wildfire and it only needs a spark. With the school holidays approaching, this is a particular cause of concern.”

Paul Embery, the London regional secretary of the Fire Brigades’ Union, said: “In my experience these fires are often arson.

“The vast majority tend to be by teenagers – it’s not the sort of thing you get pensioners doing.”

The Met Office’s “fire severity index” – a measure of the likely intensity of a fire should one occur – is set to hit level four, the second-highest ranking, across much of England this weekend for the first time since May 2011.

Karl Kitchen, a senior scientist at the Met Office, said yesterday that the index might be raised to five in some parts of the UK in the next few weeks if the dry, hot weather persists.