Silverstone have confirmed they are in a position to "accommodate all ticket holders" for Sunday's British Grand Prix.
Up to 30,000 spectators with public car park passes were advised to stay away from today's qualifying after constant rainfall yesterday left car parks resembling quagmires.
It was hoped that leaving those car parks empty for today would allow them to be in use tomorrow, when a capacity crowd of 125,000 is expected.
A Silverstone statement said:
Conditions were initially dry this morning, but hopes of an improvement in the state of the car parks did not appear particularly high when a deluge forced qualifying to be red-flagged for 92 minutes.
But Silverstone are encouraging all ticket holders to turn up for tomorrow's race, although several contingency measures have been put in place.
These include asking fans to allow plenty of time for their journey and, where possible, to travel by 4x4, motorcycle or to car share.
Due to the severe weather conditions fans are also asked to prepare for a longer walk to the circuit than usual as staff attempt to park cars safely.
They are also advised to enjoy the post-race entertainment in order to stagger the flow of traffic out of the track, while those camping are asked to wait to leave until Monday morning if possible.
Those camping should leave their vehicles at their campsite, as they will be turned away if they drive to the circuit.
Fans will be refunded for any unused Friday or Saturday tickets and Phillips admitted the financial hit could run into seven figures.
"It's going to cost us a lot of money. I honestly don't know the figure, but it could be a lot more than hundreds of thousands," he said.
A Silverstone hotline has been set up for travelling fans, with those affected encouraged to call 08443728300.
Formula 1 driver's tweeted about the earlier disruption.
On Friday, Silverstone managing director Richard Phillips issued an "unreserved apology" to fans, adding the incident almost reduced him to tears.
Mr Phillips said the financial hit is likely to run into seven figures, which for this season will potentially turn a profit into a loss.
He said organisers were in emergency meetings every two hours yesterday with the police, highways agencies, county council, emergency planning to "try and resolve the issues."
Many F1 fans have taken to Twitter to express their disappointment at the problems:
Problems started when a deluge of up to 40 millimetres of rainfall fell in a 12-hour period.
By mid-afternoon all campsites in and around Silverstone had to be closed.
With camping grounds sodden, caravans and motorhomes had to be escorted in one at a time when ordinarily they would have driven straight in, backing up the traffic.
Crucially, it is the loss of the car parks that caused major headaches for all concerned as they hope for them to dry out to re-use them on Sunday.
Phillips added: "We'll have to see where we are tomorrow, and then we'll have to have another look tomorrow about Sunday.
Even F1 supremo Bernie Ecclestone was contacted and told not to bother turning up.
Phillips said: "We dissuaded him from coming in. He was coming in by road, but he could have been five hours, I guess."