UK weather forecast latest: Britain is set to sizzle before heavy rain hits
The mercury will rocket again tomorrow and Sunday as the nation bakes in the hottest April weather for seven decades.
Clear skies thanks to high pressure wedged over the UK will bring ideal viewing conditions for the Lyrid Meteor shower which will light up the skies this weekend.
Star-gazers could see up to 10 meteors per hour with the display expected to peak tomorrow and Sunday, according to astronomers.
Supermarkets are gearing up for a party-food shopping frenzy as sun-drenched Britons mount a stampede for barbecues, garden furniture and even hot tubs.
Weather models show thermometers hitting 26C (78.8F) on Saturday with unseasonable heat on Sunday prompting warnings for marathon runners to take extreme care.
Entrants are urged to leave fancy dress at home and brace for 80-per cent humidity, soaring pollen counts, pollution and high levels of UV.
Local flooding is possible from surface water across much of England and Wales from Saturday afternoon until Sunday morning as a result of locally heavy, thundery showers
With the 1996 record of 22.7C (72.86F) under threat, bookies have started taking bets on the event possibly being cancelled.
Boiling heat will trigger an eruption of ‘convective’ thunderstorms across the country tomorrow afternoon, forecasters warn.
The Environment Agency has issued six flood alerts across southern England ahead of the deluge.
A spokesman said: “Local flooding is possible from surface water across much of England and Wales from Saturday afternoon until Sunday morning as a result of locally heavy, thundery showers.
“Land, roads and some properties may flood and there may be travel disruption.”
UK weather forecast latest: Saturday storm risk – mapped
Sweltering heat tomorrow and Sunday will bring the hottest weekend of the year so far, forecasters say.
Blistering heat hitting ground drenched after last week’s rain will force columns of water into the sky – so-called convective activity – triggering thunder, lightning and heavy rain.
Met Office meteorologist John West said southeastern England, including the capital, will hang onto the heat through the weekend as temperatures start to fall off elsewhere.
He said: “Saturday is looking very bright and sunny from the start of the day with plenty of sunshine and blue skies.
“Through the early afternoon we will start to see some heavy downpours starting in the southwest before spreading across the Midlands and central areas by late afternoon and evening and these showers will be quite thundery.
“However it is going to be very warm again and we could see 26C (78.8F) in London with temperatures in the 20Cs widely.
Flood alerts have been issued for parts of the UK
“The Atlantic will take control through the weekend which is when we will see slightly cooler conditions from the west, however the southeast will hold on to the heat on Sunday.”
Depending on cloud and rain, temperatures on Sunday will be among the highest seen during the marathon for 26 years, he said.
If clouds part for long enough in the capital, runners could be facing the hottest marathon since records began in 1910, he added.
He said: “The southeast will be warm on Sunday and after a few showers in the morning it will be largely dry.
“We expect to see 22C (71.6F) which is not far off the record for the London Marathon, the record will depend on showers and cloud cover.
“All in all it is going to be very warm and rather humid for runners with relative humidity of 80 per cent in the morning falling to around 50 or 60 per cent.
“Runners will also have to contend with high UV, pollution and pollen.”
A swathe of air laden with irritant particles and ozone from Spain and northern France will push smog levels through the roof over the weekend, experts have warned.
Defra is forecasting high pollution across the south on Saturday with slightly lower levels forecast on Sunday.
Runners face moderate levels in the capital while westerly winds will push readings to low elsewhere.
A Defra spokesman said: “Small areas of High air pollution are possible in parts of southern England, with wider areas of Moderate air pollution in the south.
“Elsewhere in the UK, pockets of Moderate air pollution are possible with most places seeing Low levels.
“Areas of Moderate pollution may persist in southeast England on Sunday, but most other areas will be Low.
“With fresher maritime weather arriving from the west mainly Low levels of air pollution are forecast for Monday and Tuesday.”
Alison Cook, director of policy at the British Lung Foundation, said: “High ozone levels can make breathing difficult, causing wheezing and coughing.
“Higher levels of pollen in the air will also cause breathing difficulties as symptoms including sneezing and swelling of the airways can put further strain on the lungs.”
London Marathon race director Hugh Brasher asked runners planning to wear fancy dress to wear what is “appropriate” for hot weather on Sunday.
He said: “It is difficult to say what someone can or cannot do.
“But if you are running with a fridge on your back, then you should be thinking about going an awful lot slower than you thought about previously.
““Do not think that you have to keep going and that there is any valour in doing that.
“his is a fun event for tens of thousands of people, three quarters of which are raising huge amounts for charity.
“We want it to stay a fun event.”
Supermarkets are stocking shelves with summer party foods and drinks ahead of the first barbecue weekend of the year.
Tesco expects to shift more than three million ice lollies; two million punnets of strawberries; two million burgers and eight million sausages.
Buyer Natalie Bastow said: “After months of rain and with temperatures set to hit 25C (77)-plus, this will be the first real opportunity Brits have had this year to get out into the garden and enjoy a barbecue with family and friends.
“Shoppers are wasting no time in stocking up for what is set to be a great few days of fun with al fresco cooking for a change.
Argos is reporting increased sales of hammocks, garden chairs, sun loungers, barbecues and hot tubs.
Spokesman Bryn Saysell said: “It’s no surprise our customers are snapping up seasonal products such as barbecues and garden furniture to make the most of the unseasonal but wonderful weather.”
Bookmakers Ladbrokes is offering 1-10 that marathon temperatures will beat records with 100-1 the event will be called off.
Spokeswoman Jessica Bridge said: “All bets are off when it comes to this year’s marathon being the hottest ever.
“With temperatures in the 20s forecast, runners will be grateful for the splash of rainfall also expected on Sunday.”
Exacta Weather forecaster James Madden said sun-lovers should make the most of the blistering temperatures with next week looking cooler in the North.
He said: “We are looking at the hottest weekend of the year so far with temperatures expected to stay in the low to mid 20Cs in the south.
“Next week will turn cooler for the northern half of the country, but there will still be some decent spells of spring sunshine on offer in among some sporadic showery activity.
“Southern areas will hang on to above-average temperatures and some decent amounts of sunshine throughout next week, in among some showers here and there.”
Met Office forecaster John West said meteor enthusiasts are in for a treat this weekend with clear skies coinciding with the Lyrid shower.
The Lyrids are so-called because their paths spread out from a spot close to the brilliant star Vega, in the constellation Lyra, according to space.com.
Mr West said: “Because we are forecasting fairly warm temperatures and clear skies it will be perfect for people to see the shower this weekend.”