A vigorous cold front is making its way across Victoria from the south-west, bringing significant rain to large areas of the state, says the Bureau of Meterology's senior forecaster Richard Carlyon.
The rain moved into the western part of the state this afternoon, and was expected to reach Melbourne this evening.
"There will be some locally heavier falls, to the north of Melbourne," Mr Carlyon said.
"Across the southern ranges we may see falls reach 40-50millimetres," Mr Carlyon said.
Most of state would receive welcome falls, he said.
"Last week we had good rain across most of the state, with two thirds of the state receiving the so called autumn break," Mr Carlyon said.
"Some places did miss out, particularly around the far west and also parts of central Victoria, but some of those areas will receive this good rainfall overnight.
"Anywhere across through the central parts of the state, right up through the north central and northern country, we may see these falls of around 15-30mm."
A farmers and graziers warning is current, due to the combination of wet weather and cold winds.
Mr Carlyon said temperatures would fall, behind the front.
"Once the rain clears, we will have quite a strong southerly air stream, which will be quite cold, with the lowest temperatures expected this year."
Most areas could expect maximums between 12 and 15 degrees.
The Bureau also issued a warning for flash flooding, due to steady rain and drains blocked with autumn leaves.