Bison FutÃ©, the government run site that monitors traffic levels, has given a black alert for the day with the first traffic jams starting at dawn and expected to go until the small hours of Sunday morning.
The worst delays in Normandy are likely to be on routes out of Paris and the Ile de France, roads leading to popular beaches and the ring road around Caen.
Parisians were warned to avoid heading out of the capital between 6 am and 1 pm on Saturday and Bison FutÃ© are advising motorists to avoid the major motorway interchanges between 7 am and 6 pm.
The expected heavy traffic is due to the fact Saturday is right in the middle of the holiday season with thousands set to leave towns and cities while others return from holiday.
Thousands of foreign tourists are also set to descend on France, from the UK, Holland and other parts of Europe to spend their summer holidays on French beaches or in the countryside.
Road works are adding to the delays and there have already been a number of serious accidents that have also added to the tailbacks and with a hot weather predicted for most of the weekend drivers are also advised to take plenty to drink in case their journey is longer than expected.
In Normandy traffic police were out on the major roads and people speeding slightly were initially being advised to slow down although anything more than this saw fined being handed out.
There has also been heavy traffic on the roads leading to ports in the UK such as Dover and Portsmouth and on the French side at Calais and Dunkirk.
By 9am there were 330 kilometres of traffic jams and that increased to 1,000 kilometres by lunchtime, according to Bison futÃ©.
On Saturday morning there were two accidents on the A28 in Seine-Maritime going from Abeville to Rouen, one on the A13 in Eure in the direction of Paris.