Nottinghamshire is set to be battered by "persistent heavy rain" for 24 hours.
The Met Office has issued a Yellow Weather Warning for rain from 3pm on Monday, September 30 till 3pm Tuesday, October 1.
Weather experts believe 20 to 40 mm of rain could fall during the period.
As much as 70 mm could fall on higher grounds.
A Met Office spokesman said: " With the ground having been left wet by heavy rain in the area this weekend, some flooding is likely."
What to expect
Flooding of a few homes and businesses is likely
Bus and train services probably affected with journey times taking longer
Spray and flooding on roads probably making journey times longer