Rain has already settled in at Mount Panorama and is expected to continue across the four days of the event.
There are also a number of flash flood warnings in place around New South Wales.
Supercars today released a statement on social media with CEO Shane Howard vowing that the Great Race will proceed as planned this weekend, despite the forecasts.
He also urged fans to prepare for bad weather if they will be trackside.
"The Repco Bathurst 1000, one of Australia’s premier outdoor sporting events will be proceeding as planned this weekend," said Howard.
"In light of the weather forecast over the coming days, patrons are encouraged to plan accordingly.
"Sessions will begin for all categories on track on Thursday and run through until Sunday’s great race.
"Off track entertainment at the top and bottom of the Mountain will also proceed as planned.
"We will act accordingly to ensure the safety of patrons and competitors at all times.
"We saw this morning thousands of fans lining Bathurst’s CBD to welcome the drivers to town at the driver’s parade and autograph sessions.
"We thank our fans who have arrived at Mount Panorama and look forward to four memorable days at the Repco Bathurst 1000."
Track action for the Repco Bathurst 1000 kicks off tomorrow.
