There's slow traffic on the A470 North Road inbound between Maindy Road and Corbett Road.
The A55 Conwy Tunnel is blocked Eastbound between J17 at Bangor Road and J18 at Llandudno Junction due to an accident involving two vehicles.
It's thought the collision occurred inside the tunnels itself.
Traffic is said to be stationary.
The A465 Heads of the Valleys Road eastbound is blocked this morning due to an overturned car.
The accident is thought to be between the A470 Ffrwd Road and A4060 Dowlais Top Roundabout. Police are currently directing traffic in the area.
There are delays of up to 40 minutes on Arriva Trains Wales between Cardiff Central and Ebbw Vale Parkway Because of a signalling problem at Crosskeys.
Police have closed one lane on the M4 Westbound between J30 (Cardiff Gate) and J32 (Coryton Interchange) due to an accident.
It is thought the accident is involving two cars and a lorry, and is partially blocking one of the lanes. It is not yet known if anyone was injured in the collision.
There's stop-start traffic for ten miles on the M4 Westbound between J38 A48 (Margam Off Slip) and J43 A465 (Llandarcy).
There's stop-start traffic for seven miles on the M4 Westbound between J23A B4245 (Magor Services) and J25A A4042 / B4596 (Newport/Grove Park Roundabout).
The A4232 Butetown Tunnel is closed because of industrial action between Cardiff Bay retail park and the Queensgate Roundabout. There's congestion Southbound to A48 Cowbridge Road West (Culver House Cross).
The A48 is partially blocked and there's queueing traffic because of an overturned lorry and spillage of diesel and hydraulic oil at the B4487 Newport Road / Cypress Drive (St Mellons Roundabout). It's on the roundabout.
There's stop-start traffic for eight miles after an earlier accident on the M4 Westbound between J24 A48 / A449 (Coldra) and J25 A4042 / B4596 (Caerleon)
There's congestion on M4 Second Severn Crossing to Toll Booths. Travel time is between 45 and 60 minutes. All lanes have been re-opened.