An estimated 16.7m leisure trips are planned over the August bank holiday weekend, with data suggesting the South West could see the worst of the jams.

The research, from RAC Breakdown research, suggests today (Friday, August 27) could see the largest numbers of cars on the roads with 4.3m leisure journeys by car planned.

That could result in a 25% increase in delays compared to a typical day in August, according to transport analytics experts at Inrix.  

Saturday will see 3.3m trips, bank holiday Monday 3m, with Sunday being slightly less busy (2.6m trips).

In addition, drivers are planning a further 3.6m trips at some point over the course of the four days.

Roads in the South West of England are expected to bear the brunt of the traffic with an estimated 3.6m trips expected to and from the region between today and Monday.

Inrix data suggests that some of the longest queues in the country could be in the South West with journey times on classic holiday routes like the M5 and A303 more than doubling at certain times over the weekend.

RAC breakdown spokesman Rod Dennis said: “It’s been an incredibly busy summer on the UK’s roads with vast numbers of people on the move both for ‘staycation’ holidays and for day trips to the sea and countryside.

“Our figures suggest this is a trend that will continue, with bumper-to-bumper bank holiday traffic expected, especially on the most popular holiday routes.”

Bob Pishue, transportation analyst at Inrix, warned drivers to expect long delays on key corridors. “Knowing when and where congestion will build can help drivers avoid the stress of sitting in traffic,” he said.

“Our advice is to avoid travelling in the afternoon – leave early in the day or be prepared for some travel times to double.”

Around 98% of National Highways’ roads in England will be free of roadworks over the bank holiday period.

A total of 988 carriageway miles of roadworks will be completed (833) or suspended (156) ahead of the bank holiday.