Drivers are facing tough conditions tonight (Monday March 11) as ice and drifting snow are making roads very slippery.
The A24 in Horsham is partially blocked and there is queueing traffic northbound between Hop Oast Park And Ride Roundabout and Broadbridge Heath Roundabout, because of an accident.
A fallen tree has closed the B2195 Harwood Road in Horsham in both directions at Roffey Corner.
There are hazardous driving conditions on the A29 in Houghton at Whiteways Lodge Roundabout, because of ice and snow, and nearby Bury Hill was closed earlier.
There are severe delays and stationary traffic on the A23 southbound between Handcross and Patcham in Pyecombe, because of ice and snow.
On the M23 there is queueing traffic southbound between J10, A2011 (Crawley) and J11, A23 (Pease Pottage). Travel time is 45 minutes.
Many other roads are proving difficult to negotiate with traffic reduced to 20mph or less.
Gritters are out in force, although strong gusting winds are sweeping new layers of snow across roads.
Police have advised people not to drive.