Saturday's meeting at Gowran Park - set to feature the Denny Cordell Lavarack & Lanwades Stud Fillies Stakes - was called due to thunder and lightning.
There was heavy rain at the track an hour before racing was due to get under way at 1.35pm, but as it began to ease, the jockeys weighed out on time.
Just as they mounted and were beginning to make their way down to the start, the rain started again, accompanied by thunder and lightning.
The decision was taken to delay the meeting, but there was no sign of conditions improving in the imminent future and officials were left with no option but to call off the fixture.
The card is likely to be rescheduled at a later date.
Clerk of the course Paddy Graffin said: "We just don't take chances with life and limb. There was a safety issue with lightning, and the whole thing was to do with lightning.
"It looked like it was set to clear, so that's why we sent them out for the first. We consulted with the riders and they all appeared happy we were going to proceed without stalls. There was a consideration for that, but there was so much of it (lightning).
"We considered Gowran Park has a beautiful parade ring with all the things you shouldn't have for lightning - trees. The lads leading the horses, there is concern for them as well.
"As a horse man, I wouldn't ask anyone to do something I wouldn't do myself.
"The camera crew were reluctant to go up on the hoist, so we could have a had a tape start but no pictures. It was just not conducive to any racing and the decision was made totally in the interests of safety."