Police are advising drivers to avoid the M25 until mid-afternoon after a lorry fire closed the carriageway on both directions in Hertfordshire.
The section between junctions 21a and 23 near the South Mimms services is expected to be closed until 3pm.
Long tailbacks have built up on surrounding roads.
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Mostly dry with clear skies tonight. A chilly start tomorrow with sunshine developing.
Mostly dry with bright or sunny spells