Narrow lanes and a 50mph speed limit are in place, with a free recovery service operating 24 hours a day. There will be additional lane and slip road closures as required, which will be carried out overnight when traffic flow is lowest.
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Monday afternoon's weather for the west of the region
Monday afternoon's weather for the east of the region
Top Gear favourite The Stig headed out on the road at a slower pace as a giant figure of the show's test driver headed across on a truck.