A road has been closed after 12 vehicles crashed in three miles.
The A24 in Horsham has been shut because of black ice.
On the A24 five vehicles crashed at 10.05am
At 10.05am on the A264 at Broadbridge Heath there was also a two-car shunt.
Sussex Police said: "Police have currently closed a three-mile stretch of the A24 southbound in the Horsham area due to treacherous black ice today.
"The conditions on the road going south from the Robin Hood roundabout just north of Broadbridge Heath to the Hop Oast roundabout north of Southwater, Horsham, have caused at least 12 vehicles to skid and crash since 9.45am. This area is now closed.
"No one has been seriously hurt. A few drivers have minor injuries and damage to their cars.
"The northbound lane of the A24 is open but traffic is heavy. Traffic trying to move southbound is being diverted through Horsham. The southbound lane is likely to be closed for another two hours."
PC Glen McArthur from the roads policing unit said: "Miraculously no one has been serious injured. The conditions on this stretch of road are pretty bad. We are advising people to either avoid the area or find another route. Drivers need to slow down. If there is frost on your windscreen then be prepared for frost and ice on the roads."
Sent your weather pictures to firstname.lastname@example.org or text 80360 and write SUPIC in the caption.
See the latest news headlines from The Argus:
- Peter Kyle and Caroline Lucas among the few MPs to vote against Brexit motion
- Tributes paid to teenage riding star killed in head-on car crash
- A Snowdog for little Niamh and a staggering £337,000 for The Martlets
- Rag 'n' Bone man named winner of Brits' critics' choice award
- Calls for the end of weekly bin collections to save money and boost recycling