As many as 18.4million could be expected to get into their cars this Bank Holiday Monday as they make their way home, the AA said.
Congestion is set to return to pre-pandemic levels, according to the British motoring association.
Large festivals taking place over the weekend, including Reading Festival, combined with the forever changing restrictions of overseas travel would create “the perfect storm” for congestion, the AA said.
Edmund King, the AA’s president, said: “There are likely to be big delays on the roads where holiday traffic mixes with sporting or shopping day trippers.
“Covid’s disruption to people’s lives is still noticeable in the 10% fewer long-distance trippers this August. The drop in longer trips might be due to the difficulty in booking accommodation away from home due to more families taking their holidays in the UK.”
Routes touted for congestion include the M25, M5 and A303.
However, the AA said many holidaymakers have driven just 50 miles of their home to their staycation for the weekend.
Places like Cornwall, Norfolk and the Kent coast could experience gridlock traffic as holidaymakers made their way home.
The warning comes as travellers on Friday faced gridlock when they tried to get away for the Bank Holiday weekend.
Just days ago, it was revealed the great staycation was more expensive than travelling abroad.
The Lake District was almost four times more expensive than Italy’s Lake Garda as the pandemic continued to push up the prices in the UK.
Accommodation at the Italian beauty spot cost £631 for two people, while in Lake Windermere it was £2,381, according to consumer group Which?.
Which? travel editor Rory Boland told The Times: “Holidaying at home has always been expensive but the situation has become far worse during the pandemic and it’s no wonder many people have felt priced out of a holiday this year.
“The reasons for these higher prices are complex, but it is hard to avoid the conclusion that some unscrupulous accommodation providers are charging over the odds.”