People looking to travel between Aberdeen and London are being warned of delays to rail services due to the high temperatures.
Services in and around the capital have had to slash their speeds over fears tracks could buckle in the heat.
And London North Eastern Railway (LNER), which runs inter-city services on the East Coast Main Line, advised customers against travelling as some services have been cancelled or delayed due to the speed restrictions between Peterborough and London King’s Cross.
The latest updates from LNER indicate a number of services to and from Aberdeen are subject to delays of around 35 minutes.
However, heavy rain and thunderstorms are also predicted to hit most of the country later today.
The Met Office said high pressure over eastern Europe and Scandinavia, combined with the position of the jet stream was funnelling hot air from Europe which had originated in north Africa.
But the kind of heatwave the country is experiencing is being made more likely, and more intense, by climate change, experts warn.
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A study from the Met Office previously showed last year’s summer heatwave was made around 30 times more likely than it would be under natural conditions as a result of human activity driving global warming.
Dr Michael Byrne, from Oxford University, said that if Thursday becomes the hottest day on record in the UK it would be “hugely significant”, but just the latest in a “torrent” of temperature records being broken in the last month.
“Not only has 2019 brought the world its hottest ever June, but in recent days countries from Belgium to the Netherlands to Germany have broken their all-time heat records. It has never been hotter in northern Europe.
“Such extreme heat poses serious health risks this week as well as uncomfortable questions about how well the UK is preparing for increasingly frequent and severe heatwaves over coming decades.”
The Government’s advisory Committee on Climate Change has warned the UK is not prepared for the increase in heatwaves that is expected with global warming.