After a warm to hot late winters day throughout the region, temperatures are expected to decrease as a southerly wind change moves north during the coming 24 to 48hrs as a front and rain band passes through NSW and clears on Thursday.

The boundary looks to become stuck over southern inland QLD. With onshore winds developing through the weekend, showers are expected to return to the coast, with some of these coming into the southern and southeast inland, though only isolated falls expected.

The more concentrated falls are expected further north through FNQ where the trade winds increase along the flat ridge which will help to propel the moisture through the northern parts of the nation during the weekend into next week.

The modelling for the medium term is well documented here, it is very tricky to pin down details at the moment with even the 5 day outlook adopting a low confidence forecast tonight with the guidance still poor.

00Z GFS Surface Pressure Pattern for the coming 16 days

After the front passing through the southeast and east of the nation tonight the weather is expected to settle down for most with high pressure dominating. The flat ridge will consolidate through the weekend and bring mostly fine and dry weather for the coming week over inland areas for now. Along the south coast, weak fronts passing over the southwest and the southeast in the early part of the weekend out west and Monday out east may trigger a few showers. But the model confidence is expected to remain low from later in the weekend with most models chopping and changing throughout the coming medium term. The highest chance of rainfall for the coming period will be tonight through Thursday and then again over the east coast with onshore winds.

00z GFS Rainfall for the coming 16 days

After tonight for most areas away from the eastern and southern coast, it is dry for a while with high pressure taking over the nation. Next major chance of rainfall on this particular run comes through WA from mid next week with a strong front emerging from the southwest and that links into moisture near a weak trough, potentially spreading a broad area of rain throughout the southern and eastern inland from later next week so at this stage it looks like a week between events for most of the south. Up north the humidity is increasing further throughout the outlook with showers about, a shift in the season is underway early this year.

00z GFS Precipitable Water Anomalies next 16 days

The PW values are still following the same song and dance, drier air flushing out the moisture over the east tonight and tomorrow, and pushing it into QLD. The weather then dry under high pressure through much of the south, the moisture relocating to the north of the nation. The pattern flip continues to evolve this week. Then the moisture returns through the west of the nation being drawn south and east via the jet stream. Moisture over the east coast remains high thanks to onshore winds persisting throughout the period. This moisture may also spread south and west through the nation from later next week.

00z Euro Surface Pressure Pattern for the coming 10 days

Latest Euro is much drier than the GFS through the entire run again this evening for next week. In fact as you go through the outlook period it is the complete opposite which makes forecasting near impossible next week. The rainfall should be over the for the south and east by the end of tomorrow with a settled spell under high pressure, we spoke about that dominance of high pressure mid month, then the weather starting to turn for the second half of the month. I am still siding with GFS and CMC in the medium term.

00z Euro Rainfall for the coming 10 days

Rainfall is lean for the upcoming week with the falls mainly coastal with vast areas of the inland remaining rain free under the belt of high pressure. Moisture may be reintroduced later next week which could bring rainfall a little further inland over the southeast states but right now the forecast is low confidence and this will change. The one consistent message is that the pattern flip that was forecast 4 weeks ago is now near complete and then we start looking towards the rainfall returning for the back half of the month.

00z Euro Precipitable Water Values next 10 days

PW values are completely opposite to the GFS in the medium term, however there is reasonable agreement in the short term with the passage of a frontal boundary this evening through the southeast then high pressure coming. Showers return to the east coast with elevated moisture levels thanks to onshore winds. Otherwise the model turns very dry through much of the inland which I am not buying at this time.

Rainfall for the next 10 days

A dry week for the inland looks reasonable with the showers expected for coastal communities from the weekend into next week, the heaviest over the FNQ coast and pockets of the Sunshine Coast. Showers may creep a little further inland along that weak trough. Otherwise the inland looks dry, I have removed rainfall for inland areas for now to reset and see what the next few days of data brings. Showers may develop later next week over the NT and Cape York.

More weather coming Thursday

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