Traffic is moving slowly on the key motorway in Somerset after a crash between Clevedon and Portishead. The backlog is concentrated between Junctions 19 (Portishead) and 20.
Vehicles on the northbound carriageways are experiencing delays.
Queues are stretching back to Junction 20 of the M5.
The event is expected to clear between 19:45 and 20:00.
Traffic analytics firm INRIX estimates travel time through where the crash occurred to be around 25 minutes.
READ MORE: M4 traffic: Long delays after hit and run leaves woman injured
The INRIX alert detailed: "Slow traffic due to earlier accident on M5 Northbound from J20 B3133 Ettlingen Way (Clevedon) to J19 A369 Martcombe Road (Portishead).
"Travel time is around 25 minutes.
"All lanes have been re-opened.
"Cleared at around 19:20."
It is not yet known how many vehicles were involved in the crash, or whether any injuries were sustained.
First reports of the collision came in at around 6:15pm on Saturday.
The Met Office had forecasted adverse weather conditions for this evening, issuing a yellow warning.
They predicted that the UK would be hit by winds of up to 80mph.
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This crash comes days after the ten-year anniversary of the M5 collision which claimed the lives of seven people.
The crash was one of the most lethal to be seen on UK highways.
Thirty four vehicles smashed into one another just before 8:30pm on the northbound carriageway at Junction 5 of the M5 on 4 November 2011.
Thick fog was blamed for the collision.
Fifty one people were injured, not counting those killed.
The collision sparked a fireball at the junction near Taunton.
Both carriages of the stretch of motorway remained shut for numerous days.