Scotland has recorded its hottest day ever as temperatures climbed to 34.8C.
The temperature was recorded at Charterhall, in the Scottish Borders, according to provisional Met Office figures, and beat an almost 19-year-old record by 1.9C.
Since August 2003, Greycrook – also in the Scottish Borders – held the temperature record north of the border when it experienced a high of 32.9C.
Mark Wilson, of the Met Office, said Tuesday was “officially the highest temperature recorded in Scotland since records began”.
The Met Office has issued an amber weather warning – for extreme heat in eastern, southern and central parts of Scotland – which is in force until midnight on Tuesday.
And, at the same time, the forecaster has issued a yellow warning for thunderstorms for areas across north-east England and the Borders which is in place until 8pm.
Elsewhere in Scotland Eskdalemuir in Dumfries and Galloway recorded a temperature of 32.3C, while in Threave, Dumfries and Galloway, the thermometer climbed to 31.2C, the Met Office said earlier on Tuesday.
Heatwaves are being made more intense, frequent and longer by climate change, and scientists said it would be “virtually impossible” for the UK to have experienced temperatures reaching 40C without human-driven global warming.
The Met Office’s chief scientist Professor Stephen Belcher warned temperatures would get more extreme in the future, and the only way to stabilise the climate was to cut greenhouse gas emissions to net zero.
The rising temperatures have seen ScotRail put speed restrictions on many services, and rail bosses have warned trains could be delayed because of them.
And the Scottish Fire and Rescue Service (SFRS) has warned that the wildfire risk in southern and eastern parts of Scotland has risen to “very high”.
It said that, in prolonged periods of high temperatures, the risk of wildfires breaking out increases.
FRS deputy assistant chief officer Bruce Farquharson said: “At this time of year, the ground vegetation is a combination of green growth, with a relatively high moisture content, and dead vegetation lying on top, which can easily ignite and spread quickly over a large area.”
Meanwhile, south of the border temperatures topped 40C for the fist time, with 40.3C recorded at Coningsby, Lincolnshire.
The Met Office said at least 29 observation sites across England have provisionally broken the previous all-time record, from Bramham, in West Yorkshire, to Charlwood, in Surrey.
