One lane is closed on the M5 in Gloucestershire in both directions between junction 12 for Quedgeley and 13 for Stroud after an accident involving two cars and a caravan.
It happened on the southbound side at 5.30am and one of the cars crossed over to the northbound carriageway.
Two lanes re-opened southbound at 10am but there is major congestion as a result of the crash.
There are queues southbound back to junction 11A for the Brockworth bypass and onto the A38.
More top news
Despite the rain, over a thousand people turned out to watch the annual Cheese Rolling races at Brockworth in Gloucester this lunchtime.
Philippa has the forecast for Devon, Cornwall, Somerset and Dorset
Philippa has the forecast for Bristol, Wiltshire, Gloucestershire, Somerset and Dorset.