January to March 2021 is likely to be wetter than average in the east and north of Victoria, with slightly increased chances for the rest of the state.
There are stronger chances for above average rainfall in regions further north, going into parts of New South Wales, and for much of Queensland.
Typically during January to March, north western Victoria would record about 50 millimetres of rainfall.
On average, the rainfall total gradually increases towards the south and east and can exceed 200mm for parts of the Otways, elevated parts of the east and the state's far east.
The first three months of 2021 are likely to be warmer than average along Victoria's coast.
While maximum temperatures are likely to be warmer than average along the coast from January to March, for the rest of the state there is roughly equal chances of warmer or cooler than average days.
At the same time, minimum temperatures are very likely - with chances of greater than 80 per cent - to be warmer than average across most of the state.
Several climate drivers are behind the wet outlook for eastern Australia.
We are near the peak of the current La Nina event, with the Pacific likely to return to a neutral El Nino-Southern Oscillation (ENSO) phase by autumn.
La Nina typically increases the likelihood of above average rainfall across much of northern and eastern Australia during summer.
Another climate driver giving us a push us towards a wetter start to 2021 is the Southern Annular Mode (SAM).
It has been positive lately and is likely to remain so, which typically favours above average rainfall for much of Victoria at this time of year.
The monsoon arrived at Darwin on December 19, which was earlier than the average date of December 29 - and almost a whole month earlier than last year at January 18.
Monsoon conditions increase the moisture availability more generally over Australia.
Water storages in the Murray-Darling Basin (MDB) are 58.9 per cent full as of December 21.
At the same time, water storages in the South East Coast division are 47.5 per cent full.
The increase in water storage levels for the MDB and South East Coast divisions during 2020 has been the highest annual increase since 2016.