The long-expected wet weather set in shortly after the sixth practice session earlier today and swiftly led to deep pooling in areas of the circuit.
TV cameras also captured footage of mud and water flowing off the concrete walls and down the steeper parts of the layout.
The Heritage Revival race took place behind the Safety Car before the Carrera Cup and Super2 races were cancelled due to the weather.
That led to speculation the single-lap dash for pole for the Bathurst 1000 would be canned, Supercars confirming that's the case 10 minutes before the scheduled start time.
This is the first time in Bathurst 1000 history that the Shootout has been cancelled.
It has now been confirmed that the grid for the Great Race will be determined from Friday's qualifying results.
"Race Control has advised that the Supercars Top 10 Shootout has been cancelled due to extreme weather, leaving the track in an unsafe condition for competition," read a statement from Supercars.
"Stewards are currently determining grid position for tomorrow's Bathurst 1000."
Supercars CEO Shane Howard revealed that there were attempts to divert some of the excess water away from some of the particularly bad areas of the circuit to allow the session to happen, but the conditions were too severe.
"Obviously we had that big downpour of rain, it had a lot in it and there was a lot of run off coming across the circuit," said Howard.
"The officials went out and gave it every chance they could and time to see if it improved and actually tried to re-divert where that main water course that was coming onto the track itself, but unfortunately there was too much there and not wasn’t dissipating and it was shooting across the circuit particularly at the exit of Turn 1, it was really bad.
"The officials deemed it unsafe to compete and obviously we can’t compromise driver safety. It is disappointing for everyone and all of our great fans that sat out there waiting for it to happen and disappointing for the drivers too."
