Britons faced uncomfortable conditions overnight as the heatwave continued to grip parts of the country.
Thursday saw Britain gripped by the second hottest day ever recorded.
But as night drew, a phenomenon known as a "heat burst", caused a spike in temperatures in the evening.
Lincolnshire saw a short and sharp rise in temperatures of 10C in just 20 minutes at around 10.20pm.
Overnight temperatures reached a muggy 32C, while thunder struck other parts if the country.
The sudden rise in overnight temperatures was caused by a collapsed thunderstorm, which quickly forced a blast of hot air down to the surface.
WOW parts of #Lincolnshire just saw a temporary 10 degree Celsius rise in temperature this evening 🌡️— Met Office (@metoffice) July 25, 2019
This was due to a #thunderstorm collapsing and bringing hot air from aloft down to the surface ⛈️
Check out this temperature curve from Donna Nook⬇️ #heatwave #UKHottestJulyDay pic.twitter.com/c0fVDbyiuV
The Met Office graph revealed that heat began rising at Donna Nook, a coastal area in the county, at around 10pm.
The temperature peaked just a few minutes later, before gradually falling again shortly after.
The weather agency also added: "Tonight's event is likely to be an example of a heat burst, a rare atmospheric phenomenon characterised by gusty winds along with a rapid increase in temperature and decrease in dew point (moisture)"
The stifling heat caused travel chaos across the country, with commuters left stranded as trains and roads ground to standstill.
And the chaos continued into Friday, with thousands stranded at Heathrow airport due to thunderstorms.
Damage and delays to the rail network will take the majority of the weekend to rectify.