The first race at Caulfield will start at 11am with the last race at 2.45pm in an attempt by Racing Victoria to avoid the peak of the high temperatures forecast for Wednesday.

The first race had already been brought forward to midday but with the temperature expected to reach at 41C, the racing body said the safety and well-being of the horses and jockeys had to come first.

RV said the eight race program, which features intervals of mostly 30 minutes, would now avoid the expected hottest part of the day.

Chief steward Terry Bailey said it was important for racing to be flexible and prioritise the safety and well-being of horses, jockeys and other participants.

"The safety and well-being of our equine and human participants is of paramount concern to Racing Victoria in reviewing meetings in hot weather conditions," Bailey said.

There will be four experienced equine vets at the course to inspect horses and monitor their recovery post-race.

There will also be a constant supply of water and rehydration sports drinks and icy poles in change rooms and at the starting barriers along with wash bays, hoses, ice water containers and cold-water drip systems to speed up the post-race cooling of horses.

The heatwave is expected to continue through the week which has resulted in amendments to the Sale program on Thursday where temperatures are predicted to peak at 37 degrees.

The last race on the card has been removed because of insufficient entries and the seven race card is now scheduled for a midday tart, finishing at 3.20pm.