A flood alert is in place this lunchtime (Monday November 4, midday) on the River Ouse and tributaries from Barcombe Mills to Newhaven Harbour.
The Environment Agency said river levels are high and continuing to rise as a result of overnight rainfall and this morning’s high tide.
The highest tide of the year was expected at 11am
Levels are expected to remain high for the next few hours and should peak during the next hour.
Low lying areas upstream of Lewes are most likely to be affected should flooding occur, the agency said.