The M5 Southbound between junctions 25 and 26 (Taunton) is expected to stay closed until at least 11am.
It's following a crash in which a man in his 20s died. Another two people have been taken to Musgrove Park hospital in Taunton in a life threatening condition. All were travelling in the same car.
Police are appealing for witnesses to the crash.
Motorists are being advised to take alternative routes.
More top news
The last dregs of the showers clear later on tonight and then it'll be a sunshine all the way.
There's a Met Office warning been issued for more showers and possible thunderstorms this evening.
There's been yet another delay in the case of the two men accused of causing the death of North Devon teenager Scarlett Keeling.