A34 southbound shut after crash near Botley Interchange
Thames Valley Police shut the southbound carriageway between Botley Interchange and Hinksey Hill Interchange at around 2.30pm.
It comes as the force recovers an HGV which has become stuck in a ditch following a reported crash with a vehicle.
Police said no one was hurt in the incident.
The force apologised for the inconvenience as it urged motorists to avoid the area for the next two hours.
It comes after warnings of difficult driving conditions on the A34 southbound caused by surface water following heavy rainfall.
Strong winds of up to 40mph were expected for the Oxford[2] area.
Oxon Travel, a traffic account run by Oxfordshire County[3] Council, has warned drivers to approach the waterlogged road with caution.
A statement from National Highways from around 3.15pm said: "There are long delays on the A34 in the Oxford and Botley area.
"A lorry has left the carriageway and a road closure is required for recovery. We are awaiting all equipment and crews to arrive before we close the road.
"We will update as soon as we are preparing to close."
Earlier in the day, a vehicle broke down on the A34 northbound near the Marcham Interchange just before noon which caused traffic to move at an average speed of 15mph.