The forecast for extreme heat has prompted officials in Victoria and NSW to make changes to race programs, including the abandonment of a meeting at Yarra Valley.

Racing Victoria initially brought forward the scheduled race times for Tuesday's Yarra Valley meeting in a bid to beat the expected hottest part of the day before announcing late on Monday afternoon the meeting had been abandoned.

"Following advice from the Bureau of Meteorology that the expected temperature has increased from 39 degrees to 41 degrees, RV, in consultation with the Yarra Valley Racing Club, has decided to abandon the meeting to ensure the safety of horses and participants," RV said.

The meeting will not be reprogrammed.

The Kyneton meeting on Wednesday has been scheduled to start at 11am with the final race at 2.30pm but RV will continue to monitor the forecast and make a final decision on Tuesday whether the meeting goes ahead.

The Corowa meeting across the border in NSW has been moved from Tuesday, when 45 degrees is forecast, to Thursday.

Victoria has a twilight city meeting on Wednesday with the opening race at Sandown scheduled to jump at 4pm and the last at 7.30pm.

Gunnedah in north eastern NSW will go ahead on Tuesday with the expected temperature 40 degrees and the Level Two heat policy in place.