More than 50 homes have been affected by flash flooding following heavy rain as the heatwave broke in a series of heavy thunderstorms.
Nottinghamshire Police said houses in Southwell were particularly badly hit by the extreme weather, while numerous properties, businesses and roads across the county were affected.
A force spokesman said pockets of standing water remain in various locations and drivers are being urged to take caution on the roads.
They are also advised to be aware that, in some areas, damage has been caused to drain covers and there is debris in the roads.
An advice centre will be opened at Southwell Town Hall later for those who need flood-related advice or assistance.
The force spokesman added: "Members of the public who have been working in flood water are reminded that hand washing is essential."
The A612 remains closed between Southwell and Thurgaton to enable urgent clean-up operations to take place.
A month's rain fell in just a few hours in some areas on Tuesday. Pershore in Worcestershire recorded 56mm (2.2 inches) of rain in a three-hour period, more than the area's 50mm average total for the whole of July, the Met Office said. Monks Wood in Cambridgeshire saw 33mm (1.3 inches) in the 12 hours to 1pm, while nearby Brampton recorded 48mm (1.9 inches) in the same period.
The Met Office had weather alerts in place for heavy rain across much of the UK on Tuesday, and more serious warnings for parts of northern England and the East Midlands on Tuesday night.
A police spokeswoman later said a lot of the water in Southwell had flowed away, but road closures were expected to remain in place because of the silt that had been deposited as a result of the flooding. Residents could seek help at advice centres and would be allowed back into their homes as soon as possible, and depending on damage caused by the water.