Heavy spells of much-needed rain are expected to aid firefighters continuing to battle heathland fires burning across the UK, forecasters said today.
Royal Berkshire Fire and Rescue Service is still tackling heathland fires which broke out in the Swinley Forest area earlier in the week, but crews across the rest of the UK seem to have tamed the majority of blazes.
Weather experts predict above average temperatures in many parts of the country over the weekend, but an outbreak of thunderstorms should provide some respite.
Police investigating the Swinley Forest fire yesterday confirmed they had arrested two youths on suspicion of arson.
The 14-year-old boys were released on bail until next month, officers said.
Between 20 and 30 fire appliances were due back at the scene of the fire today, as officers continue their round-the-clock efforts to extinguish it.
A fire service spokesman said: "In-roads are being made into this fire but obviously as the hot weather continues it is still causing a problem."
Lancashire Fire Service said almost all the moorland fires had now been extinguished, but firefighters were still at the location of two blazes.
A fire service spokesman said five appliances were at a fire in Belmont which started last Friday, while one team of firefighters were making sure a blaze at Simonswood did not re-ignite.
"Fortunately we have had some rain yesterday and it has continued throughout the night, so hopefully that will have some impact," the spokesman added.
Some 32 of the county's 39 fire stations have been occupied for the best part of a week.
Greater Manchester Fire and Rescue Service said they were still attending a fire at Turton, near Bolton, while a fire at Saddleworth had been extinguished but was being monitored by officers.
The hottest April on record, which saw only 21% of the expected rainfall in England and Wales, has caused vast areas of parched, tinder-dry land to go up in flames over the past week.
It is believed most of the fires, which have caused widespread damage to scenic beauty spots and conservation areas, were started deliberately.
Strong winds and very little rainfall has hampered the efforts of hundreds of firefighters and emergency workers, with helicopters being used to drop water in the worst-affected regions.
Tom Tobler, a forecaster from Meteogroup, the weather arm of the Press Association, said: "We had a fair amount of rain in western and northern parts yesterday and this is set to continue today with showers across Scotland, northern England, Wales and south west England.
"Central, south east England and East Anglia are going to stay dry."
Mr Tobler added: "This afternoon there will be heavy, thundery showers moving into south-west England and they will move in a north-east direction overnight.
"There will be a risk of heavy showers breaking out across most of the country on Saturday."
Crews in Northern Ireland have fought more than 1,000 gorse and forest fires in the past four days, in what chiefs said was the busiest time in 30 years.
Around 200 personnel, including soldiers, have battled 255 fires in 31 locations since Tuesday, according to the province's deputy chief fire officer Chris Kerr.
In the Scottish Highlands, wildfires broke out in Inverkirkaig, Lochailort and in Newton of Ardtoe in Salen, while the National Trust for Scotland said at least £100,000 of damage had been caused to its forest regeneration project in Torridon and Kintail.
Meanwhile, the RSPB warned that fires could have affected up to 40% of the English population of twite, which is a type of finch.
In England, nesting twite are confined to the South Pennines, where around 100 pairs nest in small colonies.
An RSPB spokesman said: "Even before these fires, the twite was one of England's most threatened birds. But blazes have possibly affected more than a third of the English population."
"This could be a devastating setback and England's most threatened finch has been hit hard by these fires."
Experts have predicted a "Spanish plume" over the weekend, with warm air moving in from Spain and triggering thunder storms and heavy rain across the country.
Mr Tobler added that the mass of moist, warm air would cause a mixture of sunshine and heavy rain on Saturday and Sunday with temperatures reaching the mid 20s.
"It's going to be very warm. We are expecting temperatures to get up to 25C today, and over the weekend close to that but a few degrees lower," he said.
"Today there will be mostly sunny spells and then later tonight there's a risk of some showers.
"Tomorrow will see more sunny spells but continuing risk of heavy showers and thunder storms across most of the country.
"By tomorrow night, the central and western areas of the UK are likely to get a decent amount of rain," he added.