Sussex Police has warned drivers to take care, after heavy overnight rain.
The force said there were ‘major flooding problems’ for motorists across West Sussex this morning (January 17).
The eastbound lane of the A27 near the Portfield roundabout has been closed and there have been long delays.
A spokesman for Sussex Police said: “Some drivers have ignored warning signs or have got stuck after driving into water, adding to the difficulties.”
He added drivers should be aware of the condition and think carefully before taking to the roads.
As well as the A27 at Chichester, the A23 is closed between Bolney and Pease Pottage leading to ‘extensive tailbacks’.
Also the A24 at Broadbridge Heath, Findon and Dial Boast, as well as the A29 at Bury Hill, near Pulborough.