About two million people will travel abroad this Easter, with Thursday expected to be the busiest day for traffic and for airports.
In contrast to last Easter, when travellers faced snow and bitterly cold weather, temperatures this year could reach 19C (66F) in parts of southern England over the weekend.
It is also estimated 10 million drivers will take to the roads over the holiday period.
The Highways Agency has suspended some roadworks on English motorways and major roads but some remain in place.
On the railways, passengers on a number of routes face service suspensions while a £55 million programme of engineering work goes ahead. The West Coast Main Line and London's Liverpool Street and Waterloo stations will be affected.
P&O Ferries will carry 132,000 passengers on its Dover-Calais route from Good Friday to Easter Monday - an increase on the 98,000 figure last Easter.
A total of 200,000 passengers will travel with the Channel Tunnel high-speed Eurostar train company in the period to Easter Tuesday.
The most popular spots for those heading abroad include the Canary Islands, Turkey, Egypt and Tunisia. Long-haul destinations that are likely to see plenty of Britons include Florida and Cuba.
The RAC said that 33% more people intended to take short trips by road this Easter than last Easter.
Forecasting busy roads on Thursday and on Good Friday, the RAC added that all major routes were likely to be congested, with the heaviest traffic being on the M25, the M1 and the M6. The AA said resorts such as Brighton and Bournemouth could be busy as well as historic cities such as Cambridge and Edinburgh.
