M4 Weather News
Why we show the weather. We publish official weather warnings and forecasts from the Met Office beside our M4 traffic news. People come to us to check the road before they set off, and the weather can change that journey as much as an accident can. Wet roads mean it takes at least twice as far to stop. Ice, fog, strong wind and heavy spray all leave less room for mistakes. Our aim is simple: to help everyone who uses the M4 stay safe and decide how, and when, to make their journey.
Alongside the weather we show live accidents, closures and roadworks, and our M4 trends pages show how busy the M4 is from day to day and hour to hour. Together they give you the whole picture before you set off.
Weather along the M4. The M4 runs west from London past Reading, Swindon and Bristol, over the Severn into Wales, and on past Newport, Cardiff and Swansea. Our M4 weather page follows the Met Office warnings for London, the South East, the South West and Wales, the whole way along the road.
The Prince of Wales Bridge carries the M4 high over the Severn estuary, one of the most exposed places on the motorway. In strong winds there can be restrictions on the bridge, so check our live news before you cross.
Wind on wide motorways
Much of the M4 is now three or four lanes wide, and long stretches have become smart motorways. That's a lot of open tarmac, with the barriers and verges that would normally break up the wind set further apart. On a windy day gusts can sweep across the carriageway with little to stop them. Take extra care if you're driving a high-sided vehicle, towing a caravan or riding a motorbike, and give them room if you're passing.