UK weather: the heat goes on. It could be the longest hot spell in a decade Motorists reported a ridge forming in the road while others spoke of cars "ploughing into" the melted road surface. Saturday's top temperature made it the hottest day since 2009, when the mercury reached 89.6F (32C) in Hampton, London, the Met Office confirmed. A heatwave is defined by the Met Office as a continuous period where somewhere in the UK has a daytime temperature of 82.4F (28C) or above. The last time somewhere failed to hit such heights was on July 6, meaning the UK has now had nine days of unbroken hot weather - the longest period of consecutive sunshine since July 2006, when the UK bathed in 16 days of glorious heat. Charlie Powell, a Met Office forecaster, said Greater London could expect to see temperatures of around 86F to 88F (30C to 31C) this coming week. He said it was "not out of the question" that the UK could exceed Saturday's temperature, but added that Britain could be on course to beat 2006"s 16 unbroken days of hot weather. He added: "I think we will see high temperatures lasting until the last week of July, early few days of August, but they will be increasingly confined to the south of the UK. It will become a bit more changeable towards the start of next month. It doesn't mean we will have a washout, just something which is more normal for this time of year. Brighton beach on Sunday morning (Connors Brighton) He said that any thunder showers towards the middle of next week "will be few and far between," and would be around the middle of the country, particularly near the Pennines. The hot weather has had its drawbacks. Crowds arriving on Brighton beach yesterday were met with rubbish strewn across the sand left over from Saturday's sun-seekers. Retailers and supermarkets reported booming sales as shoppers spent thousands of pounds on barbecues, food, sunscreen and garden furniture. Asda said sales of barbecues had risen by 204 per cent in the past two weeks; charcoal and fuel is up by 176 per cent. Emergency services warned against swimming in open waters and quarries after three people died in the West Midlands in the past week. John Woodhall, a water-rescue specialist with West Midlands Ambulance Service, said: "Quarries are not like swimming pools. You go from 28C [82.4F] outside to 10C [50F] in the water. Even strong swimmers can slip under water and you may not make it back up again.