A "hazardous weather" warning has been issued for the county as storms bring a dramatic end to two weeks of sunshine.
With dry ground and hot temperatures, the arrival of the storms could mean flash-flooding and hail as well as high winds.
Leicester Mercury weatherman Dave Mutton said the weather would feel a lot fresher after the storms had passed through.
He said: "We're going to see a lot of rain over Wednesday and possibly hail. It could be quite dramatic.
"Later in the week I'm expecting maximums much lower than we've been used to recently and it will feel a lot fresher.
"Usually the British summer is two fine days then a thunderstorm but we've managed two fine weeks this summer.
"It's the longest spell of dry weather in Leicestershire since 2006."
The Met Office yellow warning is for thunderstorms "with very heavy rain, hail and gusty winds".
Up to 30mm (1.2ins) of rain is expected.
Dave said: "At this point the ground is very dry and hard, so run-off can be extensive and flooding may be a problem."
The next few days will see temperatures ranging from about 15C (59F) to 25C (77F).• See the five-day forecast for Leicester and Leicestershire.
