Heavy showers and thunderstorms are set hit Nottinghamshire.
The Met Office has released a yellow warning for rain which could result in flooding.
The warning is expected to stay in place until Saturday.
The Met Office chief forecaster said: "A warm and humid airmass covers southern Britain at present.
"This is already becoming increasingly unstable and producing a few thunderstorms through Thursday, but these are expected to become more widespread overnight into Friday and extend further north.
"Many places will miss the worst of these - some may stay dry - but where they do occur, 20-30 mm rain may fall in a short time, leading to some surface water flooding, whilst lightning and hail may be additional hazards."
