Fashionable racegoers are set to shiver through the coldest Melbourne Cup in a decade.

Temperatures are expected to hit a top of just 16C on Tuesday, with a cool southerly breeze making it feel colder and showers expected in the morning, the Bureau of Meteorology says.

"It will be a cool Cup Day and will probably be the coldest since 2006," senior forecaster Rod Dickson told AAP.

Showers are also expected for the morning, but should clear in time for the race that stops a nation.

"It will be cool and grey morning but there will be a bit of sunshine... it should be quite a fine afternoon," Mr Dickson said.

The weather is expected to clear from Wednesday and the weekend is expected to be sunny and warm.

COLDEST MELBOURNE CUP DAYS:

* 15.8C in 2006

* 15C in 2001

* 13.6C in 1995

* 11C in 1913, the coldest Cup day on record, with showers and hail.

SOURCE: Bureau of Meteorology