Temperatures are expected to drop to between 20C and 25C as the Championships get underway on Monday, but spectators are encouraged to wear suitable clothing and bring sun cream.Fans are allowed to bring empty refillable bottles into the ground this year and the number of refill stations and fountains has been increased to more than 100.But the heatwave is set to be short lived, with an Atlantic front forecast to send highs dropping to 25C on Sunday, 22C on Monday and just 19C on Tuesday.Simon Partridge, a forecaster with the Met Office, said: “There’s extreme heat in Europe and heat got across to the UK, with highs pushing towards the 35.6C June record.”More and more heat is being pumped north from Africa through Europe, with highs in France again in the 40s.”But heat will be shunted away from the UK on Sunday as an Atlantic front brings cooler conditions.” Network Rail said: “Rails in direct sunshine can be 20C hotter than air temperature. Rails expand as they get hotter and can start to buckle. Speed restrictions are imposed as slower trains exert lower forces on the track, reducing the chance of buckling. At the same time daytrippers clogged coastal routes as they headed for the seaside, including the A23 to Brighton, A31 to Dorset, A30 to Cornwall and M55 to Blackpool.More than 30,000 UK breakdowns were expected on Saturday, with call-outs set to have doubled in tourist areas according to the RAC.More than 150,000 visitors were expected in Brighton, 75,000 in Bournemouth, 75,000 in Great Yarmouth and 50,000 in Blackpool. Competitors take part in the annual Round the Island Race, a 50 mile circumnavigation of the Isle of Wight, starting and finishing in CowesCredit:Patrick Eden Photography Festival-goers at Glastonbury have been warned to stay hydrated and wear sunscreen by organisers as it looks to topple its record of 31.2 C in 2017.At the Wimbledon Championships, the heat rule has been expanded and will for the first time apply to men as well as women in the singles matches.The rule allows a ten minute break to be taken between certain sets when the heat stress index is at or above 30.1C and one player requests it.Judy Murray is among those who had complained that male players should also benefit from the rule, saying last year: “In men’s singles you are having to play five sets, you could be out there four or five hours. It is very important to protect the health of the players.” Rails overheated and roads began to melt on Saturday as the record heat took its toll on the nation’s transport infrastructure.Speed restrictions hit Britain’s rail network to prevent rails buckling as temperatures hit 34C, making it the hottest day of the year after Friday’s then-record 30C.With thousands of people heading for beaches around the country travellers were warned to plan ahead to avoid delays.Network Rail said rail tracks absorb the heat, with their temperature typically rising to 20C above the surrounding air temperature, forcing trains to slow down to avoid the danger of rails buckling.In Northern Ireland Translink Rail was forced to cancel services after rails reached temperatures of 49C and trains had to be stopped from running over a section of track near Carlisle station.Thameslink and Great Northern also saw trains forced to slow between Cambridge and Hitchin, and the east coast main line between Peterborough and London King’s Cross.There were also speed restrictions in the London area, between Three Bridges and Earlswood, London Victoria and Balham, London Bridge and East Croydon, and between Stratford and Maryland.It comes after speed restrictions were imposed all week between London Waterloo to New Malden, causing delays on busy commuter routes. Festival-goers keep cool during day four of Glastonbury Festival at Worthy Farm, Pilton, SomersetCredit:Leon Neal/Getty Images, Europe “Keeping passengers moving is always our top priority. But we want people to be prepared. Where soaring temperatures do lead to us having to put in place slower speeds for safety reasons, please bear with us as our dedicated teams of engineers work to fix the problem. It may mean your journey takes longer over some portions of your journey. We’d also remind passengers to carry some water with them so they don’t get too parched.”Some parts of the country saw roads softening as temperatures shot up.Gritters have been deployed in some areas to spread crushed rock dust to create a non-stick layer between the surface and vehicles’ tyres, with the AA warning that roads begin to soften at around 27C.Cumbria County Council said: “Our gritters are on call. Roads are 20C hotter than the air and melt at 50C.”The Communication Workers Union shared pictures of roads damaged by the heat, with one taken by a post office worker on Exmoor showing a stretch of melted road with tyre impressions in the softened surface road at Heasley Mill, near North Molton, Devon.Drivers have been advised to use warm soapy water to clean sticky tar from their vehicles. Want the best of The Telegraph direct to your email and WhatsApp? Sign up to our free twice-daily Front Page newsletter and new audio briefings.