Brighton and Hove faces a day of wet and windy weather tomorrow (Wednesday 20 October).
About half an inch of rain has been forecast to fall, with wind speeds approaching 30mph and gusts nearer 50mph at times.
The Met Office issued a thunderstorm warning for a large part of the south – but with the worst of the storm over the south west.
The official forecaster said: “A brief period of heavy rain, thunderstorms and very gusty winds may cause some disruption on Wednesday morning.
“There is a small chance that homes and businesses could be flooded quickly, with damage to some buildings from floodwater, lightning strikes, hail or strong winds.
“Spray and sudden flooding could lead to difficult driving conditions and some road closures.
“Where flooding or lightning strikes occur, there is a chance of delays and some cancellations to train and bus services.
“There is a slight chance that power cuts could occur and other services to some homes and businesses could be lost.
“There is a small chance of damage to trees by strong and gusty winds.”
