The Met Office has issued a yellow weather warning for thunderstorms covering York and North Yorkshire.
The alert comes into force at midnight on Thursday (1 August) and ends at 11.59pm. Along with heavy showers and thunderstorms, the additional hazards of hail, gusty winds and lightning are also possible.
The conditions are expected to develop for most of the UK and may lead to some disruption, including difficult driving conditions, power cuts, flash floods and travel delays.
A Met Office spokesperson said: “The heaviest showers could result in 20-30 mm within an hour, with 24 hour accumulations possibly reaching as much as 70-90 mm where multiple showers affect the same location.”
Meanwhile, a yellow heat health warning has been issued across most areas of England by the UK Health Security Agency.
This is in place until Wednesday, and covers all areas of England other than the North East and North West.
The UKHSA warned that expected hot weather may have “significant impacts” on the health and social care sector