Cambridge University Botanic Garden have claimed temperatures in the area soared to 38.7°C yesterday – which means it could be the hottest day ever recorded in the UK.
The Met Office are now investigating the provisional figure and will confirm whether the record was broken in the coming days.
Cambridge was already confirmed as the hottest place in the country yesterday, setting a new record for the warmest July day ever.
The National Institute of Agricultural Botany (NIAB) published a reading of 38.1°C in the city.
But today it was announced that a thermometer in the Cambridge University Botanic Garden weather station had reached 38.7°C.
The current record for the hottest UK day was set on August 10 2003 at Brogdale near Faversham in Kent, with a temperature of 38.5°C.
A Met Office spokesperson said: ‘A new provisional value of 38.7°C has been submitted from Cambridge Botanic Garden that will require further quality control and analysis as part of our routine practices.
‘The Met Office observation network uses a number of different types of data collection in collaboration with a range of partners. Not all provide real time data.
‘As the official source of meteorological statistics for the UK we take the quality of our recordings very seriously and will not confirm the new record until the quality control process has been completed, this is likely to be early next week.’
The Cambridge University Botanic Garden has been open to the public since 1846.
It currently houses a collection of 8,000 plants, trees and shrubs from all over the world.