The bureau is predicting the wild climate will ease simply in time for the principle occasion.
“The heaviest rain for Cup Day is predicted within the morning,” senior forecaster Michael Efron mentioned.
“We’ll see the rain changing into extra intensive n the early hours of Tuesday and it will proceed till about 11am … we might see [up to] 15 millimetres in these few hours.
“Nonetheless, the situations appear to be they may clear up round lunch time which is nice information for these heading to Cup Day.”
Melbourne is forecast to succeed in 20 levels on Tuesday, and whereas will probably be cloudy and moist, it can even be extraordinarily sticky with excessive humidity additionally making a danger of thunderstorms within the afternoon.
“The additional moisture within the air from the humidity is what’s inflicting the rain,” Mr Efron mentioned.
“However the situations will turn out to be cooler later within the afternoon as a chilly entrance strikes in and southerly wind comes by way of.”
And simply because Melbourne climate likes to maintain us all guessing, Mr Efron urged punters to additionally pack some additional clothes for the large race.
A wintry blast is predicted to maneuver in throughout the state late Tuesday night time as low stress system sweeps the state.
“We’re solely anticipating a prime of about 16 on Wednesday and it’ll really feel loads colder as a result of there will likely be contemporary westerly winds and the prospect of hail and thunderstorms,” he mentioned.
“We’re even anticipating some snow to develop in elevated elements of the state together with the Grampians because the chilly air strikes in.”
Nonetheless, the clouds are set to half, and will probably be a partly sunny and dry 18 levels on Oaks Day.
Temperatures are anticipated to creep again up into the low 20s by Friday, with the mercury tipped to hit a heat 21 levels on Saturday for Stakes Day.
Melissa Cunningham studies breaking information for The Age.