Today is expected to be the busiest day on the south's roads so far this year as millions of people set off for their Easter break.
Bank holiday getaway journeys mixed with commuter traffic today will lead to the heaviest congestion of the weekend, it has been predicted.
Drivers have been urged to consider delaying their journey until the afternoon of Good Friday, when traffic is expected to be relatively quiet.
The A31 through the New Forest and all of the M3 are predicted to be the worst affected roads today.
There is also expected to be disruption on the railways due to an extensive programme of engineering works over the weekend.
A poll from VisitEngland showed that around 3.4 million Britons are set to take an Easter break in the UK involving at least one overnight stay, providing an £800 million boost for the UK economy.
Around 6.5 million Britons are planning day trips over the holiday period, with a further 9% undecided whether to have a break involving an overnight stay, the survey revealed.
VisitEngland chief executive James Berresford said: ''Easter is a fantastic time of year to spend a short break or day out with the family exploring the wonderful destinations in England.
''The industry has rallied following the severe weather earlier this year. It's business as usual for tourism with a full line-up of events and offers across the country, and destinations ready and waiting to welcome visitors this Easter break.''
Tomorrow is forecast to bring the best weather of the Easter break, with dry and sunny skies across the UK.
Bill Payne, a forecaster for MeteoGroup, said: ''Although today will be very warm, with highs of 18 degrees, it will turn cloudier throughout the day.
''It means Easter Friday will be the nicest day of the Easter break - although a little cooler, it will be dry and bright everywhere.
''There will be a few showers around on Saturday but the weather really changes on Easter Sunday and becomes quite unsettled. There will be some heavy rain in England and Wales with showers lasting into Monday.
''But it will be quite different in Northern Ireland and Scotland where it should be dry and sunny.''
An estimated 1.6 million Britons are heading abroad for the holiday.
Over the Easter weekend, 370,000 passengers will leave from Heathrow Airport, 200,000 from Gatwick, 120,000 from Stansted, 60,000 from Luton and 4,500 from Bournemouth.
Thousands will take ferry services to the continent and the Channel Islands from Weymouth, Poole and Portsmouth.
The engineering work on the railways will affect services to and from a number of major hubs, including London's Charing Cross, London Bridge, Paddington and King's Cross stations.
Southampton Central is among other major stations where services will be affected over the weekend.