Victorian racing officials are bracing themselves for a deluge at Flemington on Saturday, adding more misery to what VRC chief executive Dale Monteith says is already the wettest Spring Carnival in 13 years.

Melbourne has received 76mm of rain in October, with some forecasts suggesting as much as 50mm could fall on parts of the city on the weekend alone, meaning the Flemington track is likely to be very heavy for the Victoria Derby on Saturday and the 150th running of the Melbourne Cup on Tuesday.

''It's been the worst weather we've had in 13 years and we're expecting more on the weekend - but I suppose the forecasts can be wrong,'' Monteith said, with more than a hint of optimism.

While Monteith said he did not expect the sort of extreme hailstorms that battered Flemington during the Australian Cup in March, the forecasts for Derby Day were not exactly promising. ''The start to this carnival reminds me of the ‘traditional' wet springs in the early 1980s,'' he said.

The Gai Waterhouse-trained Descerado won this year's Caufield Cup on a rain-soaked track, which had only just been upgraded from the heaviest rating of a Dead 10. Mudlarks Harris Tweed and Monaco Consul filled the minor places from the fast-finishing Melbourne Cup favourite Shocking.

The poor forecast could result in a raft of late scratchings with Metal Bender's trainer Chris Waller already flagging the prospect of withdrawing his horse from the Melbourne Cup if weather conditions don't improve.

Monteith said racing was an "all weather sport," and the expected heavy conditions could play to the advantage of the international raiders who have experience on heavy tracks in Great Britain and Ireland, such as Manighar, Profound Beauty, Bauer and Illustrious Blue.

Crowd favourite and 12-time Melbourne Cup winning trainer Bart Cummings is expected to have three runners in the ‘race that stops a nation', being Dariana, Precedence and the Cox Plate winner So You Think, all of whom prefer a faster track.

And those race goers who are brave enough to brace the conditions at Flemington won't even be able to marvel at the synonymous rose garden, which Monteith said should be at prime condition for Thursday's Victorian Oaks.

Along with the international horses, Monteith said dignitaries from 27 countries attending the Melbourne Cup will not be put off by the weather.

In comparison, crowd figures were well down at the rain-soaked Caulfield Cup, resulting in a large financial loss for the Melbourne Racing Club. While the Melbourne Cup is still expected to draw a large crowd, the weather could see that number well below the magical 100,000 of recent seasons.

The wet start to Spring has played havoc with sports of all kinds, with many cricket matches in Victoria being called off due to the frequent rain over the past month.