M4, A40 and A55 live congestion updates as holiday ‘weekend of woe’ begins on roads

Motorists are being warned of delays on the M4, A40 and A55 motorways in Wales as the busy summer period begins. Motorists are expected to make around 27 million car journeys in the coming days, with Friday the busiest day.

Traffic Wales issued congestion warnings on the M4 around Newport and near Swansea on Friday. Holiday traffic is also slowing traffic on the A40 in Carmarthenshire and the A55 in north Wales.




An accident on the M4 westbound at junction 40 at Port Talbot caused delays and just after 4pm there were delays of 50 minutes on the M4 westbound at Brynglas Tunnels.

Chaos also reigns for anyone travelling to France this weekend, following a spate of arson attacks on railway lines. Eurostar passengers are being urged not to travel after French rail services were hit by “malicious acts” just hours before the Olympics opening ceremony.


Several Eurostar trains to Paris have been cancelled and others diverted. The rail operator, which operates international services from London’s St Pancras station, confirmed on Friday that its trains would be delayed due to ongoing problems across the Channel.

The disruption comes just hours before the Paris 2024 Olympics open and as millions of people embark on summer getaways.

Follow live traffic updates below:


Traffic jam on the M4 westbound in Carmarthenshire

Motorists are advised to allow extra time for their journeys if travelling west along the M4 in Carmarthenshire.

Traffic jams on the A55

Motorists are being warned to allow extra time when travelling on the A55 due to congestion on the westbound side between junctions 24 and 23.

Delays at Brynglas Tunnels with journey time of 55 minutes

There will be delays in the Newport area around the Brynglas Tunnels on Friday afternoon.

According to traffic monitoring service Inrix: “Delays on M4 Brynglas Tunnel westbound before J26 A4051 (Malpas Road). Journey time is 55 minutes.”

Congestion warning for traffic leaving Cardiff

There is now a heavy traffic warning as you exit Cardiff.

Traffic Wales advises that there are delays on the A4232 northbound.

Traffic cameras show long delays

Traffic cameras show that there is particularly high traffic in the Briton Ferry/Port Talbot area.

There was an accident on the westbound carriageway earlier. The situation was resolved quickly, but there are major delays in both directions.

(Image: Traffic in Wales)

Vehicle fire causes delays

Delays in the Brynglas Tunnels heading west are now 40 minutes.

A vehicle fire on the A55 North Wales motorway is also causing traffic jams in Conwy, heading west. The incident happened just after Abergele junction 23A.

Long delays in both directions at Port Talbot

There was an earlier accident on the M4 at Port Talbot westbound.

The situation has been cleared for some time but there are still long delays in both directions in the area.

Here are the queues on the eastbound carriageway at the Briton Ferry Bridge.

(Image: Traffic in Wales)

Congestion points at 1 p.m.

Here are the main congestion points at 1 p.m.:

  • Traffic jams due to an accident on the M4 westbound before J40 Port Talbot. Traffic jams until J38 Margam
  • Traffic jam due to holiday traffic on the A40 westbound at the A4242 (Pontlesneven roundabout).

  • Delays on the M4 Brynglas Tunnels westbound before junction 26 of the A4051 (Malpas Road). Journey time is ten minutes.

  • Stop-start traffic on the M4 eastbound between J30 A4232 Pentwyn Link Road (Cardiff Gate) and J26 A4051 (Malpas Road).

  • Stop-start traffic on the M4 eastbound between J42 A483 (Swansea East / Briton Ferry) and J41 (Baglan / Pentyla).

  • Traffic jams on the M4 Prince of Wales Bridge in both directions between the M49 junction and the M48 junction. In the roadworks area.

  • Traffic jams on the A55 Britannia Bridge westbound after J9 A487 (Port Dinorwic). Journey time ten minutes.

30 minutes delay on the M4

Friday afternoons are always busy on the M4 around the Brynglas Tunnels and after a quiet morning, queues start to form.

Westbound delays in the area of ​​Junction 26 at the tunnels are approximately 30 minutes.

M4 update after crash

Update on this accident on the M4 at junction 40 in Port Talbot. The vehicles involved have been moved to the hard shoulder and have reopened, but traffic has been halted for a period of time so that the accident can proceed safely.

This means there is congestion on the westbound carriageway up to junction 38 at Margam.

The Inrix traffic monitoring system says: “Just before 12:20 p.m., all traffic was stopped to move vehicles to the hard shoulder and reopen all lanes.”

Accident on M4 causes delays

There has been an accident on the M4 in the Neath Port Talbot area.

One lane is closed westbound just before junction 40 at Port Talbot. Traffic is blocked in the area.

(Image: Traffic in Wales)

Congestion alerts for M4 Newport and Swansea

Here’s the latest news from Traffic Wales, the organisation that monitors our main roads.

They are warning of traffic jams in Newport and the Swansea area.

Congestion warning on the M4

After a quiet morning on the M4, traffic is starting to pick up.

A red alert has been issued for congestion between Cardiff and Newport. The Inrix traffic monitoring system is warning of delays eastbound between junction 30 Cardiff Gate and junction 26 Malpas Road at the Brynglas Tunnels.

This is from the camera located near junction 28 of Tredegar Park.

Traffic jams on the M4 on Friday morning(Image: Traffic in Wales)

3.2 million trips will be made today

Traffic is expected to peak on Friday as commuters compete for road space with at least 3.2 million drivers making leisure trips to airports, holiday trips home and day trips.

Traffic jams continue with 3.6 million and 2.9 million additional journeys expected on Saturday and Sunday respectively.

Second most popular summer destination for almost 10 years

Back in the UK, the RAC has predicted that 13.8 million motorists in the UK will embark on leisure journeys between today and Sunday.

According to the estimate, this weekend would be the second busiest summer holiday weekend since 2015.

Behind only 2022, when 18.8 million people took to the roads in the middle of a heatwave and after two years of lockdown due to the coronavirus.

Eurostar customers urged to cancel trips

Eurostar customers have been urged to cancel their journeys where possible after “coordinated” acts of vandalism caused disruption in the run-up to the Olympic Games in France.

The rail operator, which runs international services from London St Pancras, confirmed on Friday that several trains to Paris had been cancelled and others had been diverted or delayed due to the ongoing problems over the Channel.

Eurostar publishes updated information

Eurostar said: “Due to coordinated acts of malicious intent in France, affecting the high-speed line between Paris and Lille, all high-speed trains to and from Paris are being diverted via the conventional line today, Friday 26 July.

“This adds about an hour and a half to the journey time. Several trains have been cancelled.

“Eurostar teams are fully mobilised in stations, in call centres and on board to ensure that all passengers are informed and can reach their destination.”

“Everything points to arson”

The incidents paralyzed several high-speed lines linking the French capital to the rest of France and neighboring countries, according to Transport Minister Patrice Vergriete.

Speaking on BFM TV, he described people fleeing the scene of the fires and discovering incendiary devices, adding: “Everything suggests that these were arson attacks.”

Dover Port Information

There was no update this morning, but they are expecting a very busy weekend.

This is the last advice they have published.

Series of fires along railway tracks reported

French rail company SNCF said a series of incidents overnight had affected travel to and from London across the Channel, to Belgium and across western, northern and eastern France.

Three fires have been reported near the tracks of the French high-speed lines Atlantique, Nord and Est by local media.

What Eurostar said

This is what Eurostar told its passengers on what is likely to be one of their busiest days of the year:

Due to coordinated acts of malice in France, affecting the high-speed line between Paris and Lille, all high-speed trains to and from Paris are being diverted to the classic line today, Friday, July 26.

This extends the journey time by about an hour and a half. Several trains have been cancelled.

Eurostar teams are fully mobilised in stations, in call centres and on board to ensure that all travellers are informed and can reach their destination.

The company said customers were being informed by email, text message and on the Eurostar website.

Any affected passenger can cancel or refund their ticket or change their trip free of charge.