MEDIUM TERM OUTLOOK - THE JOYS OF SPRING FORECASTING

I have had some interesting debates on my social media feed by non paid members clearly, who are aghast to the inaccuracy of the weather modelling at this time of year and are horrified that their forecasts can go from 1 months rainfall to nothing overnight. Well no surprises here, that is likely to continue and if you have come back daily to this particular discussion, we have been talking about that for quite a few days now.


I wish I could offer you more confidence in the forecasts, but the reality is for those looking for more rainfall in the east, once we see a low pressure system develop along the trough in SA/NT during Friday afternoon into Saturday and can track that front through the southeast and how fast that ends up moving, the confidence will remain low, until those two elements start to be resolved.


Now for the west of the nation, there is a high chance of below average temperatures next week, for a good chunk of the state while the north bakes. A cold front responsible for that will spawn the secondary event next week over southern and eastern Australia with the chance of severe thunderstorms breaking out.

Lets take a look - a reminder these medium term forecasts are later due to the data sets also coming out later.


Moisture Watch This Week - October 7-14 2021

The main moisture to watch this week is coming through the NT at the moment and then gets picked up by a trough and low this weekend and propelled east. The main moisture impacts are likely to be felt through NSW and QLD, that said rainfall is likely to develop further south but lighter falls. There is another system over the southeast at the end of this period which may tap into this same moisture source over the eastern inland.

Moisture Watch Next Week - October 15-22 2021

The moisture becomes more widespread over the north from later next week into mid month with more storms. So expect to see the north of the nation yellow most days until April. Two ports of moisture to watch, again a feed off the easterly winds coming through the interior with another trough to lift that into a rain and storm event for NSW, QLD and possibly VIC and inland rainfall coming into southern NT and northern SA. Another surge of moisture passing through Indian Ocean may be projected through the southeast of the nation, could spark storms over northern and central WA.

Rainfall This Week - October 7-14 2021

A lot of this to come down from the weekend into early next week for central and eastern areas. Patchier falls through SA and VIC, and more moderate rainfall through QLD and NSW with a strip of heavier rainfall expected to form somewhere along the NSW/QLD border extending back into the southern NT and north to the tropics. The SWLD of WA sees a strong front which may bring a few showers early next week. That system forms the secondary system this time next week over the southeast.

Rainfall Next Week - October 15-22 2021

The start of this period sees showers and storms over the southeast states, some possibly severe. The eastern and northern inland remains unsettled with troughs forming. Some of those could become widespread along the east coast. Coverage of storms increasing over the north and the shower activity over in the west very limited with high pressure aloft and at the surface.

Rainfall Anomalies Next 2 weeks - October 7-22 2021

The anomalies largely unchanged from yesterday and you can see the influence of that moisture running through northern Australia and then that moisture deviating towards the southeast and east.

Wildcard Systems

Watching the east coast closely in the next 2 weeks for a coastal trough or low pressure system which may produce heavy rainfall or severe weather, the main focus of this is for NSW during this period. Also the surge of moisture over the northwest of the nation may spark storms and showers across the central and western inland of WA. These being signaled in the second week of the outlook.

Temperature Anomalies This Week - October 7-14 2021

Cooler than average weather for much of the southwest and marginally cooler than normal elsewhere under clouds and rainfall.

Temperature Anomalies Next Week - October 15-22 2021

Moderating cooler bias over the southern parts of the nation though conditions may be still below average over the southeast with persistent cloud and rainfall. And ridging over the west will continue to keep temperatures down with southwest to westerly winds. The north warmer than normal with higher humidity values.

REFER TO THE VIDEO AT THE TOP OF THE PAGE FOR MORE


18Z GFS - Surface Pressure Pattern and Rainfall Distribution - Next 2 Weeks

18Z GFS - Precipitable Water Anomalies - Next 2 Weeks

18Z GFS - Rainfall Accumulation - Next 2 Weeks

12Z Euro - Temperature Anomalies - Next 10 days

12Z Euro - Simulated Satellite- Next 10 days

I was going to update La Nina conditions today but waiting on a bit more data to come through which is slow to arrive but will talk more about that tomorrow - for now the focus is on the short term and refer to the Indian Ocean Outlook at the top of the page too for the impacts of that driver in the coming weeks.




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