Roads have been closed across Welwyn Hatfield and Poters Bar by floods. (Image: Archant)
The M1 has now reopened southbound between J8 and J6 following an earlier accident.
The motorway was closed in both directions between J7 and 6a after a car overturned on the slip road for the A414.
The driver of the car has been taken to hospital by ambulance.
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