MEDIUM TERM FORECAST - ACTIVE PATTERN CONTINUES FOR THE FORTNIGHT.

Busy busy in the weather office tracking all the model madness, but the overwhelming signals from modelling is that large scale weather systems coupled with deep moisture surging in from the northwest and north, as well as via easterly winds as the high pressure systems continue to shift further south through to their summer time position.


Lets take a look at all the action and see whether we can have some of our questions answered.

Moisture Watch This Week - October 12-19 2021

Moisture is clearing the central and western interior from today and you can see that with clear skies. Moisture shunted back to the tropics from tomorrow though another impulse may begin to drift south and be drawn through QLD with upper level westerly winds. There is moisture hanging back from this current system over NSW and QLD with that moisture being drawn southwest ahead of a trough sparking the rain and storms from tomorrow and Thursday once again over the east. Modest moisture wrapped into the low moving over SA will be replaced by colder drier air. And a deep moisture plume from the Indian Ocean is expected to bring up rain chances next week over the SWLD.

Moisture Watch Next Week - October 19-26 2021

The moisture continues to sweep in from the northwest to southeast across the southern states and the moisture building up over the northern and northeast inland of the nation, with scattered afternoon and evening showers and storms becoming more widespread with random falls. A larger scale rainfall event is possible on the east coast with onshore winds and over the southeast inland after a hot few days.

Rainfall This Week - October 12-19 2021

Rain is ongoing over the eastern inland and that moves east. We have rain developing over the southeast inland and southern parts of the nation Wednesday with severe storms. Severe storms and scattered areas of rain will redevelop for eastern QLD and NSW for Thursday and Friday. Moisture snaps back into the NT and Cape York with a few showers and storms, more productive over the Top End. Then watching the west coast of WA where there may be a system bearing down this time next week.

Rainfall Next Week October 19-26 2021

Moisture hanging back over much of the inland will be waiting for lifting mechanisms to see rain become widespread, there has been some indication of inland troughs over QLD and the NT and a few heat low wafting through the interior. But confidence is a low still. Showery for the east coast and over the southeast inland very late in this period after what is a warm to hot few days. Lingering rain from the previous week may be ongoing over the SWLD then trending drier.

Rainfall Anomalies Next 2 Weeks - October 12-26 2021

Lots of green on the broad does not indicate elevated chances of above average rainfall, especially where thunderstorms are involved but you can see the areas likely to see unsettled weather during the coming 2 weeks. Higher probabilities of above average rainfall over the southeast with this low passing through until weekend, the SWLD where the cold front passes through potentially next week with deep moisture attached and the tropics are active and ahead of schedule.

Temperature Anomalies This Week - October 12-19 2021

Cooler signals easing for WA with the winds shifting into the east during Wednesday but the southeast expecting a large scale cold core trough with multiple small scale low pressure systems to drive a wintry blast over southern and southeast Australia in the coming days. Already below average temperatures have been observed under thick cloud these past few days. The north is warm and sultry with that air shifting further north during the week with the southwest flow shunting the heat away by the weekend.

Temperature Anomalies Next Week - October 19-26 2021

The heat rapidly returns into next week with a long fetch northwest flow dragging in the very warm and dry heat from the outback into the southeast inland. This will approach the coastal areas of QLD and NSW but the air likely to modify by the time it reaches this location. The heat intensifies under an upper high over the tropics and the west turns cool with a strong westerly flow from an anomalous system later in the previous week lingering through this period before the weather warms up again.


DATA

Refer to the video at the top of the page for all the discussion points.


18Z GFS Surface Pressure Pattern and Rainfall Distribution - Next 16 Days

18z GFS Precipitable Water Anomalies - Next 16 Days

18z GFS Rainfall Accumulation - Next 16 days

12z CMC Rainfall Accumulation - Next 15 days

12z Euro Rainfall Accumulation - Next 15 days

More details on the storm outbreak, severe weather potential for the south and east in your state based forecasts this evening. Harvest forecast coming up at lunchtime.