Wednesday: Dry, warm and sunny. Rain then snow tomorrow, snow Friday and Saturday with 25 to 60 cm on the way. More rain then snow next week.
A ridge of high pressure lies to our east, letting it warm up today.
Then the next big low and cold front arrive with a long stretch of precipitation for the rest of the week. It will bring rain to start on Thursday morning, but then it is cold enough for the rest to be snow, with 25 to 60 cm by the time someone has won the AFL Grand Final.
Dry and warm again on Sunday with the high out to our east, before the next snowy stretch. Rain changing to snow on Monday morning, then a series of cold fronts could produce snow through to next Wednesday.
It all comes down to a simple equation. To make it snow you must have: low pressure, moisture and cold enough temperatures.
We can guess the moisture part of the equation for the season ahead by looking far away from the alpine areas, and considering the balance of warm and cool water in both the Pacific and Indian Ocean.
Pacific Ocean: El Nino is over and we will have a Neutral or La Nina phase instead. Neutral would be a good source of moisture, and La Nina would be a great source. La Nina would also work to push it towards the alps.
Indian Ocean: a negative Indian Ocean Dipole (IOD) is the most likely situation for this winter. This means that the waters off Indonesia are warmer than the waters off Kenya, meaning more moisture for us to play with. And the atmosphere responds to this imbalance, by pushing it towards the alps.
So, that, combined with warm waters off much of the coastline of Australia, all works to ensure the moisture part of the equation is as good as it can ever be.
But, what about the low pressure and temperature parts?
These are the big questions for 2016. We don’t have any good guidance to show how many low pressure systems will move through, and whether they will take a helpful path. And, all this warm water around us means that our air temperatures may be warmer rather than cooler.
My feeling is that we will have several ridiculously huge dumps of snow (thanks to high moisture), producing some absolutely epic days this season. But what happens in between those only time will tell…