News

Jul 2014
24

Borderline cold enough for 5 to 10 cm snow up high Thursday/Friday. The stagnant pattern will change next week, with more snow on the horizon.

Summary:

A low pressure system should be near Mt Gambier on Thursday night, southwest Tasmania on Friday night, then east of Tasmania on the weekend. The low is weakening, after peaking back to our west earlier in the week. It is only borderline cold enough for snow up high, but most of the moisture has gone anyway. So, we are looking at light snow above 1700 metres Thursday, then 1600 metres on Friday. As the low passes us by on Saturday, the precipitation will come up from the southwest for a time, but there is not much in it at all. 

The next high pressure system moves over New South Wales on Saturday, making cold fronts slide down to our south into early next week - but check the outlook as this pattern will change.

Outlook:

The high stays in control, making cold fronts fall away to our south. This is a sign of a negative Antarctic Oscillation (or the Southern Annular Mode) - where cold fronts struggle to move across the southeast of the country. Good news is that the forecast for the Oscillation, is heading into positive territory again:

Antarctic Oscillation

A cold front should build south of Western Australia mid-next week. There is a gap between the high pressure systems (good for access to tropical moisture) but the low centre driving the system is not 'cut-off' from the westerly airflow at this stage (no wrap around moisture, limiting precipitation). So this should be a moderate fall of snow ahead of next weekend, with lots of cold air in behind the front.

Commentary above courtesy of Jane's Weather.  www.janesweather.com