“Energetic” thunderstorms are set to strike Derbyshire, weather forecasters have warned.
The Met Office said low pressure is expected to clash with humid air – sparking heavy storms.
A thunderstorm alert for Derbyshire is valid from Monday night until Wednesday.
A Met Office spokesman warned: “Large rainfall totals, falling in short periods and on to hard-baked ground, may lead to localised flooding, with hail a possibility.
“The public is advised to take extra care and be aware of the risk of localised disruption to travel and more generally to summer holiday activities.”
Temperatures are set to turn cooler towards the end of the week after weeks of hot weather.