Motorists are being urged to stay patient during the bank holiday rush in and around Leeds.
Thousands of extra cars are expected on the roads as people leave the city for the weekend and arrive for the Leeds Festival.
Diversions and road closures will be in place for the festival, as well as the West Indian Carnival in Chapeltown on Monday.
Inspector John Sanderson, of the eastern area roads policing unit, said: “This weekend is hugely busy, because of the carnival and the festival, both of which involve large traffic operations.
“People need to be patient, be prepared and stay safe.”
The Highways Agency said it would help holidaymakers by ensuring that 98 per cent of England’s motorways and other main roads are roadwork-free.
More than 150 miles of roadworks will be suspended between Friday and Tuesday, including 18 miles of improvements to barriers on the M1 between junctions 39 and 42.
Director of traffic management, Simon Sheldon-Wilson, said: “This will be a great help to people travelling during the holiday – more lanes will be open and many speed restrictions will also be lifted.
“Highways Agency traffic officers and the police will work to clear up any incidents as soon as possible but we advise drivers to check weather and travel conditions before any long journey.”
This evening and Monday afternoon are expected to be the busiest periods, he said.
Meanwhile Leeds Bradford Airport was expecting a 12 per cent increase in passengers, with an estimated 30,000 people expected to fly out on the last summer bank holiday of the year. Turkey, Cyprus and Spain are the top destinations for holidays, with Amsterdam, Paris, Berlin and Dublin also popular.
Tony Hallwood, the airport’s marketing director, said: “We also look forward to welcoming overseas visitors to experience the region’s culture, history and famous hospitality.”