Thunderstorms could bring torrential rain, large hail and strong winds to Sheffield, forecasters warn.
This morning the Met Office has issued a weather warning for large parts of northern England.
On Thursday temepratures are set to reach 31C in Sheffield but the heat and humidity could set off some dramatic storms on Friday.
The warning - which is in place between 2pm and 11.45pm on Friday - states: "Whilst many places are likely to remain dry, there is the potential for thunderstorms to develop during Friday afternoon, lasting well into the evening.
"Where these occur expect torrential downpours with a much as 30 mm of rainfall in 1 hour and 60 mm in 3 hours.
"Large hail and strong, gusty winds will be additional hazards."
There is also a small chance of flash flooding and power cuts.