But the question still remains, who sees the best of it? Who sees any potential flooding? Who sees the severe weather elements? Who misses out?

These are the questions that are likely to remain unanswered for a while as we wait to see where the remains of Tiffany makes the turn to the south and becomes absorbed into the upper northwesters and spreads the moisture and heavy rainfall east and south.

Many factors need to come into play before the moisture comes further south; the timing of the short wave through the southeast next week, the position of the high pressure ridge to the south of the country, the speed of the tropical moisture spreading southeast from the northwest etc. It is simply too early to tell.

For now the focus is on the heavy rainfall impacting the northwest of the nation, the severe storm outbreak continuing for parts of eastern Australia and then the potential return of more general rainfall across the heart of the nation and then into the east.

Lets take a look


Rainfall Next 10 Days

Remains of low confidence nationwide as we wait for the moving pieces to come into play within real time observations. At this stage the signals are strengthening for rainfall to sweep from the northwest of the nation through to the southeast with heaviest falls likely staying through northern and eastern WA, through northern SA into northern NSW and much of QLD. There may be easterly winds that combine with the trough as it moves in with the moisture from Tiffany and enhanced rainfall along the NSW coast and adjacent ranges next week, cannot be ruled out, but there area defined will change as we go along. The tropics remaining active with showers and gusty storms right through the period and reduced heat levels after the very high values recorded in recent weeks.


The divergence of modelling renders forecasting specifics ahead of time very low confidence. But, the weather is expected to turn more humid and unsettled with widespread rainfall and thunderstorms moving south and east from the Kimberly through the southern and western NT and then into Central Australia. From there, the models go as you can see, all over the place. So watch this space. Areas in yellow are the areas to be impacted the greatest on current guide but this will refine.


Most models agree on turning the moisture south with the remains of Tiffany from the northwest of the nation south and southeast throughout the nation. That is a very high chance of occurring. The element to watch is the high pressure system to the south, does that ridge in and deflect the rainfall through to QLD and northern NSW or does it move south or remain weak enough, that the trough and moisture can sink south throughout SA and into VIC? That question still remains unanswered at the moment, though the signs are strong on certain models, DO NOT be lured in by the myriad of data sets and the like just yet. The forecast remains low confidence.

Flood Watch NT and WA

Flooding is possible from today through the weekend over the Top End and Kimberly. The risk will likely spread through the interior over the weekend into next week and charts for outback areas into SA will be issued ahead of time. The Central Top End has dodged a bullet which is great news even with the minor flooding in pockets overnight.

Thunderstorm Forecast Friday

Thunderstorms from today are expected to continue overnight and transition to elevated thunderstorms are weaken below severe thresholds later this evening. Thunderstorms will progress slowly east along the slow moving trough, making it towards the GDR by dawn with further thunderstorms expected to form from sunup through NSW. For Victoria, thunderstorms are expected to continue this evening and redevelop from the late morning over central districts, really from Melbourne metro northwards to the NSW border and points east. Thunderstorms more likely turning severe about the eastern third during the afternoon and evening. The risk will progress further northeast through NSW during the evening, but a onshore northeast flow will keep coastal areas mainly stable, with heavy showers still about.

Flash Flood Risk Friday

Heavy rainfall is likely with thunderstorms that develop in the viewing area tomorrow, really from any time of day. Thunderstorms may produce more intense bursts of rainfall over the southern inland of NSW, extending into northern VIC and across to about the ACT. Some areas could see 50mm+ in an hour.

Damaging Winds Risk Friday

Damaging winds are possible with the more organised thunderstorms during the afternoon and evening on Friday. Outflow winds of 100km/h are also possible in areas not impacted directly by thunderstorms, which could fell trees.

Large Hail Risk Friday

Large hail is a risk in multicellular storms during the afternoon and evening, once again in those areas not impacted by morning thunderstorms where the air can become more unstable. This will be over the central inland of NSW and along the GDR up to the northern tablelands.

Tornado Risk Friday

Slim risk of a weak tornado through the inland of NSW with sufficient shear to produce a few rotating thunderstorms.

Thunderstorm Forecast Friday

Thunderstorms contract slowly eastwards on Friday with the low deepening along a trough over the southeast. This will create a dynamic environment for thunderstorms to turn severe, all modes of severe weather is possible with the chance of some giant hail and destructive winds in a few storms. Thunderstorms will stretch into QLD but these will be less severe than further south. Strong storms continue for northern Australia, some severe with heavy rainfall leading to flash flooding.

Thunderstorm Forecast Saturday

The remains of Tiffany is expected to move southwards and merge with a trough over inland areas of the nation leading to more widespread showers and thunderstorms developing during the day with locally heavy falls leading to flash and riverine flooding. The same can be said for the east with storms continuing from Friday into Saturday and this will contract was through the day, with further thunderstorms likely to form, leading to all modes of severe weather possible for QLD, NSW and the ACT. Clearing conditions through VIC. Afternoon storms possible near a developing heat trough over in the west and gusty showers and thunderstorms possible over the Top End.

Thunderstorm Forecast Sunday

Thunderstorms will continue over much of northern Australia with the remains of Tiffany being drawn into a deep trough triggering widespread convection. Thunderstorms possibly severe over a wide area of the interior with heavy rainfall the main issue. There may be damaging wind gusts further towards QLD.

DATA - Refer to video for more information and details and the day by day breakdown with GFS

12Z Euro - Surface Pressure Pattern and Rainfall Distribution - Next 10 Days

The pressure pattern is becoming more dynamic for the east and north of the nation through the coming week. Even for central parts of the nation there is the risk of well above average rainfall with flood potential. The rainfall forecasts over the east could also lead to flooding. Tropical weather remaining very active with a trough nearby and the chance of some further tropical lows forming in the next 10 days. The onshore winds over the east will support more widespread rainfall developing right through next week, so numbers while they will bounce around, I do expect there to be another 1-3 months worth of rainfall across parts of VIC, NSW and QLD. Rainfall also intruding into parts of SA with moderate falls for the east and north. For now, dry weather for much of WA, but this could be altered depending on the movement of low pressure through northern and eastern areas.

12Z Euro - Precipitable Water Values - Next 10 Days

I think this is a dead give away as to what we can expect across the nation through the next week and where the rainfall is likely to go. The values being forecast by this model is the highest values they have been all season. The PW values are nearly 300% above normal in some areas, and that leads to excessive rainfall and severe weather events. So a heads up for those in QLD, NSW and VIC with the risk of flash and riverine flooding increasing further. While it is the weekend coming up, I will have another look at the flood potential throughout Saturday and Sunday as we move into next week. The moisture profile is increasing for SA which will generate more rainfall and that will be also seen through inland parts of WA. And you can see the moisture hanging up over the tropical north with elevated moisture levels with a trough deepening.

12Z ICON - Rainfall Accumulation - Next 8 Days

More information can be found in the video

12Z Euro - Rainfall Accumulation - Next 10 Days

More information can be found in the video

12Z CMC - Rainfall Accumulation - Next 10 Days

More information can be found in the video

12Z GFS - Rainfall Accumulation - Next 10 Days

More information can be found in the video

12Z Euro - Rainfall Accumulation - Next 15 Days

More information can be found in the video

12Z GFS - Rainfall Accumulation - Next 16 Days

More information can be found in the video

More on the 6 week outlook coming up later this morning if not lunch time today.

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