FOR SOUTHERN AUSTRALIA, THE SIGNALS FOR RAINFALL ARE IMPROVING.

Very quick update on the fast flow pattern next week with the theory I was talking about last week of moisture streaming into the fast flow wave pattern is looking to produce widespread rainfall opportunities in about 7-8 days time.


Now the rainfall distribution will continue to fluctuate from run to run, but I am fairly confident in this latest update from GFS this morning for next week.


While we have a mainly dry week for SA and western inland parts of NSW and northwest VIC, this will change next week. Remaining western and eastern areas will likely see multiple bouts of rainfall.


GFS 18z - Surface Pressure Pattern and Rainfall Distribution - Valid Monday 5th of July 2021.

The pressure pattern stable this week as we have spoken about and that will continue into the weekend while the east gets another soaker and another large scale cold front and cloud band brings rainfall to WA. But then southern areas of the nation from SA through VIC should see an increase in rainfall with frontal systems. Watch that large moisture incursion associated with a low pressure system developing over WA. Now while I think a low developing from that region is unlikely, I am looking at the rainfall signal coming out of the northwest as being the continuous signal expressed by the medium term modelling. This moisture/rainfall looks to impact large areas of the inland mid month.

GFS 18z - Precipitable Water/Moisture Values next 2 weeks - Valid Monday 5th of July 2021.

The precipitable water values tell a good story with the upcoming fortnight with widespread wintry weather over the south of the nation with moisture rolling in over the top of this wavy flow, but being drawn into the cold fronts from time to time. The wild card is another northwest cloud band and trough that comes out of the deeper tropics. That would set the stage for major rainfall to break out mid to late month. Something to watch.

GFS 18z - Rainfall for the next 16 days - Valid Monday 5th of July 2021.'

Significant shift in the modelling on rainfall which makes sense in relation to the pressure pattern above and the moisture available - this will change but it is a good signal from the models that the Indian Ocean moisture is likely to be in play next week.

I will have more on this during the afternoon and I full expect the system to not be there but the moisture content in the atmosphere is increasing with each run, for the period the 12-19 of July.





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