Colder air has filtered through the eastern and southern inland in line with a trough and front moving over the region during the past 24 hours. A new high is coming in to send the southern and eastern inland into a frosty spell, but look lovely days to follow with near seasonal weather to develop. won't last long, with a period of windy, wintry weather which develops over southwest Australia from later today and persists through the week, that long wave will gradually move towards the east later this week and then set up camp!

Signals are increasing in the medium term for a large long wave to be parked over southern Australia and then southeast Australia into mid month bringing a pretty wintry spell, and it may bode well for the snowfields who are desperate for some luck to go their way.

Temperature Anomalies - Valid July 12th to July 19th 2021.

A cold airmass spreading over southern and southeastern Australia as the long wave trough moves from west to the east, sending up strong cold fronts and a deep layer of cold air from the southwest.

Significant frontal weather under the current guide would then contract from WA through the southern and southeast areas of the nation mid week.

GFS 18z - 500mb/18000ft flow pattern - Valid Sunday 4th of July 2021

Showing the deep colder airmass spreading from the west the potential for the coldest weather of the year settling over the southeast mid month, that has been in line with the climate outlooks here on this particular site and in line with the climate drivers. It is now appearing in the short to medium term forecast products.

GFS 18z - Surface Pressure Pattern and Rainfall distribution - Valid Sunday July 4th 2021.

The fast flow pattern is strengthening on the modelling - and that signal is strengthening not just on GFS but other global forecasting products. We will track that over the course of this week.

Snowfalls for the period over the next 10 days are returning but still below average for what one would expect for this time of year during this period.

Euro Snowfalls for the next 10 days - Valid Sunday 4th of July 2021.

I will be posting snowfall charts coming up this week, just waiting to see how the pattern settles by Tuesday.

The GFS forecast for snowfalls during the coming 2 weeks, showing that deep cold burst of weather, and if that was to verify, settling snowfalls from the Grampians through central VIC along the NSW ranges would be possible, with over a metre of snowfalls for Alpine resorts. Sea level snowfalls would also be possible for TAS. But this is likely to change, the atmosphere, warm a tad being that this is 10-12 days out from beginning.

GFS snowfalls for the next 16 days - Valid Sunday 4th of July 2021.

This is quite a good look if you are a snowfan, but CAUTION should be advised reading data that runs into the medium term. I do think that we will see a cold blast as the long wave passes from west to east, but HOW cold remains to be seen but below average temperatures are highly likely and has to phase with moisture to produce widespread snowfalls.

GFS rainfall for the next 16 days - Valid Sunday 4th of July 2021.

Note the rainfall is filling in over SA and connected through to the Indian Ocean which is what one would expect with the moisture off the west coast. Heavy winter rainfall for coastal areas of southern Australia are increasing in likelihood but again we can drill down into specifics as we get closer to each system.

More to come.

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