The M25 is closed in both directions in Hertfordshire because of a lorry fire and smoke blowing across the carriageway.
The section affects is between junction 21a for London Colney and junction 23 for South Mimms and the A1(M).
The Highways Agency says the road is expected to re-open from 3:00 pm.
More top news
Any early morning mist will clear to leave a dry and cold day but with some sunny spells.
Clear spells overnight will lead to widespread frost and ice, with a few mist patches by Sunday morning.
Police are appealing for witnesses after a female pedestrian died following a hit and run collision in Essex.