All going to script today with moist unstable airmass shifting east, drier air rolling through the eastern inland with high pressure beginning to take control of the weather for much of the inland of the nation.
The west is quite cool today, well in relative terms for October with a few showers drifting through after a gusty wet day yesterday. For the south that front is expected to bring showery weather later in the day for SA, starting with the EP tonight and then spreading throughout the southeast areas tonight and into Sunday.
The southeast turns showery again Sunday with front rolling through setting the scene for a cold start to the week for the southeast. Another front is expected to bring another burst of showery weather to the SWLD later Monday into Tuesday. Then that system will run across the south of the nation during mid week.
Moisture over the north will begin to build up over the north with a few showers and thunderstorms for the Top End, Kimberly and western Cape York. The moisture is expected to run south throughout the nation later next week into the second week of the month.
That is when we will likely see the next rain event move south and east - AGAIN the preliminary bias is for QLD, NSW and VIC with this one.
Rainfall for the next 10 days
The rainfall has contracted to the south and southeast of the nation for the coming week, the rainfall light and patchy but may accumulate to moderate falls. The north turning more tropical with scattered falls about, most areas picking up 10-20mm this week. The wildcard system this week is whether the moisture from the north can get brought into the upper trough to produce storms over NSW and QLD mid to late week, the models are split on this. Spring time weather is volatile so expect this chart to change.
Temperatures Next 2 Weeks
No change from yesterday's run - the models in reasonable agreement in keeping the seasonal to below seasonal values across the south and above seasonal values over the north.
October 2-9th 2021
12Z GFS - Surface Pressure Pattern and Rainfall Distribution - Next 2 Weeks
Rainfall is easing over the east, we see the system over NSW being pushed off by a series of cold fronts during the coming week. So that will render much of the nation settled. The last front in the sequence which passes through during Wednesday to Thursday brings the next chance of rainfall for the southern and eastern inland, with a band of showers of storms making it through SA, VIC, NSW and southern QLD. The north of the nation very humid and unsettled from mid week and you can see that moisture coming down through Central Australia from the second week of the month, that will see widespread showers and storms return for the southern and eastern states. The west may see a reduction in rainfall after mid week with temperatures on the rise.
12Z GFS - Precipitable Water Anomalies - Next 2 weeks
Good moisture supply over the east will leave and then we have generally seasonal values over the next week or so with frontal weather passing through and picking up some of that moisture from the north. The larger impulse of moisture coming through from the north occurs later next weekend into the following week with rainfall chances coming up and I do think we will see the bias of rainfall for southern and eastern parts of the nation once again.
The north, humid!!!
12Z GFS - Precipitable Water - Next 2 Weeks.
Note the shades of yellow and orange over the north - that is PW values of 50mm+, so there is plenty of humid weather to come as we go through the month, over eastern and southeast parts of the nation in particular. A large pulse of this moisture looks to make it's way into QLD during this period. This will see another round of storms come back into the forecast.
12Z GFS - Rainfall Accumulation - Next 2 Weeks.
Watch that moisture through the central interior for you needing rainfall in the south and east in the second week. For the first week of the period, rainfall is over the southern parts of the nation for the most part and across the tropics each afternoon, especially NT.
12Z CMC Ensemble - Rainfall - Next 2 Weeks.
Curiously this model continues to bring significant moisture through mid month over central and eastern areas of the nation - in line with GFS. Something to watch this week.
12Z Euro Ensemble - Rainfall - Next 2 Weeks.
Again the bias of rainfall looks to be over the east, but there is good agreement of moisture coming from the tropics through southern and eastern areas of the nation from mid month.
Rainfall Anomalies - Next 2 Weeks
Watch this space - there are some more volatile weather events to come in the next 2-3 weeks.
More to come this evening.