In a final push to finish off road improvements, night-time road closures will be in place for five days at the double junction near Elm Grove and The Level.
Since the end of August, workers have been changing junction layouts where Lewes Road meets Elm Grove and Union Road.
The council said the aim is to prevent traffic queuing at red lights from obstructing vehicles trying to pass, and to improve the pedestrian and cycle route between Lewes Road, Elm Grove and the Level.
The final five-day phase from Monday (November 20) will see new road surfacing and markings put in place. To enable this, certain junctions will be closed between 8pm and 5.30am.
On Monday and Tuesday there will be no entry or exit between Lewes Road and Union Road. On Wednesday and Thursday there will be no entry or exit between Lewes Road and Elm Grove.
It is hoped no works will be needed on the Friday – but the date will be used if bad weather causes an overrun, the council said.
Signed diversions will be in place and drivers are urged to find alternative routes. Pedestrian routes will be maintained. Bus journeys could be affected after 8pm and passengers should check with operators.