This is my last snow forecast for 2016. I hope they have been useful for all your endeavours. See you again (snow-wise) in 2017.
Friday 30 September: Snow, snow and more snow. Happy end to season 2016.
A complex area of low pressure is crossing the southeast today and tomorrow. It produces persistent snow today then lots of start and stop snow showers tomorrow.
Its dry and warm on Sunday with a high out to our east.
A cold front crosses through early Monday with rain late Sunday into Monday morning, then it changes to snow and persists through the day. Another cold front brings more persistent snow on Tuesday, then we are done.
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…