Roads to popular tourist destinations are expected to become congested as the bank holiday getaway begins.
The AA has estimated 23.4 million car journeys will take place on Friday.
It highlighted likely traffic blackspots to include routes heading towards east coast destinations such as Skegness, the M4 from London towards Wales, and the M6 towards the north-west coast.
The RAC expects leisure traffic to peak on Friday and Saturday.
The Port of Dover in Kent, which is preparing for 18,000 travellers between Friday and Sunday, warned the busiest periods each day will be between 6am and about 1pm.
Saturday will be the port’s busiest day of the year so far, with more than 8,000 travellers.
Strike action and engineering work will cause disruption on a number of routes on Britain’s railways.
Walkouts by members of the Transport Salaried Staffs’ Association on Friday and Saturday in a dispute over pay will affect West Midlands Railway (WMR) and London Northwestern Railway services.
Timetables will be slashed on both days, including no WMT trains after 7pm on Friday or before 7am on Saturday.
Network Rail engineering work means parts of key intercity lines will be shut.
High pressure builds this weekend, bringing plenty of fine, settled and very warm weather as temperatures rise ☀️🌡️ pic.twitter.com/vENM4zEX4X
— Met Office (@metoffice) May 21, 2026
The East Coast Main Line will be closed between York and Darlington from Saturday through to Monday.
Buses will replace trains between Newport and Bristol Parkway from Saturday for two weeks.
There will be no Thameslink services through central London between Saturday and Monday, affecting services to Gatwick and Luton airports.
Travel trade organisation Abta said there will be a surge in families heading off on holiday this weekend as it marks the start of half-term breaks for many schools.
It reported strong demand for short-haul sunshine holidays in destinations such as mainland Spain, Italy, the Balearic and Canary Islands, and Portugal, as well as city breaks in Milan, Nice and Barcelona.
Meanwhile, parking app company RingGo said its analysis of recent bank holiday periods found Saturday is likely to be the busiest day of the long weekend at coastal towns and cities such as Bournemouth, Hastings and Torquay.
It said seaside towns are “consistently outperforming inland locations” during bank holidays in terms of the number of parking sessions recorded.
The Met Office has forecast a heatwave in some parts this weekend.
Temperatures are set to peak on Monday when 33C could be recorded in southern England and the Midlands.
