Derbyshire could be hit with floods as weather forecasters predict 8cm of rain to fall in one day.
The whole of the county is on alert after the Met Office issued a yellow weather warning for heavy rain.
The warning is in place between 8am and 10pm on Friday, August 16.
A Met Office spokesman said: "Rain is expected to become widespread and heavy at times during Friday.
"Heavy rain may also coincide with peak travel times during the afternoon and early evening leading to difficult driving conditions on major routes.
"The heaviest rain is most likely over high ground, where some places may see 60-80 mm.
"Strong winds are also expected with 30-40 mph gusts likely around exposed coasts and hills."
The Met Office said residents should expect flooding on roads, homes and businesses and bus and train services may be affected.