The risk of severe weather impacts over many areas of the nation, headline todays forecast.

The trough over the south and southeast of the nation will be the focus of severe thunderstorms, with heavy rainfall leading to flash flooding and damaging winds the main risks over a lot of VIC and through western and southern NSW.

We have already seen Mildura record 4 times the monthly average overnight, some areas recording 3 months worth of rain through parts of VIC. 52mm at Glen Inness in NSW. Seen around 200mm near Townsville and 100mm near Hughendon. It is wet.

The monsoon trough which is now reached it's southern most point over WA, NT and QLD will merge with the northern flank of the trough over the southeast and produce days of heavy rainfall and flood potential. Severe flooding is possible with widespread falls of 100-200mm possible over the Outback where these locations only get 150mm of rainfall in one year!!

So significant disruption is expected from the flooding over Outback areas.

A tropical low is expected to form in the monsoon trough as it begins to shift northwards through the weekend, this being the focus of severe weather risks with intense rainfall and dangerous flash flooding. Squally winds also a chance over interior parts of the NT and the Kimberly down to Broome.

Squalls and storms over the NT will also increase in coverage and intensity Friday through the weekend. Damaging winds are possible.

In the east over the weekend, severe thunderstorms with all modes of severe weather is possible with heavy rainfall the highest risk. That will extend into northern SA over the weekend into next week.

Another trough will develop over the southeast on Monday and link up with moisture and lead to another wave of showers and thunderstorms with heavy falls developing once again with a flash and riverine flood risk.

On the east coast of NSW and QLD, watch the trough moving northwards and combining with the onshore flow mid to late next week with heavy rainfall a chance of developing in these zones if the pattern allows.

It is busy.

Lets take a look


Rainfall Next 10 Days

The coverage of rainfall remains largely unchanged from last night, use the rainfall as a guide as the distribution is likely to be uneven in distribution, some areas getting more than what is shown here, and less than what is shown here, in the same zone! So just be aware of that through northern, eastern and southeastern areas of the nation. The weather turning wetter over the northern tropics thanks to the deepening monsoon, that rainfall guide carries a higher confidence. The tropical low that forms may produce falls close to 500mm during the coming 10 days. The monsoon also likely to produce 200-400mm during this period over the northern Top End and through Cape York. The moisture from the tropical north is expected to spread south and east into Central parts of the nation which could lead to severe flooding in communities. The moisture from the tropical low may move southwest into the central interior of WA bringing some of the first rainfall of the Summer for some places. The weather in the east, tricky to forecast accurate rainfall with thunderstorms about in the short term. The weather over the east coast could turn very wet with onshore winds and the trough stalling along the coast leading to frequent showers and storms with heavy falls. The weather drying out over southern parts of the nation with a southerly flow to develop with the trough moving into NSW.

Thunderstorm Forecast Thursday

Thunderstorms will redevelop over VIC and NSW in more widespread fashion, isolated over eastern SA and through central WA on Thursday. Thunderstorms likely to turn more severe over VIC and NSW with heavy rainfall and damaging winds the main concern there. Thunderstorms will cover much of the NT where intense rainfall may be observed and dangerous flash flooding to develop. The north, gusty storms may develop in more numerous numbers as a tropical low forms over the NT.

Thunderstorm Forecast Friday

Thunderstorms will redevelop along a slow moving trough over VIC and NSW once again with storms turning severe with heavy rainfall leading to flash flooding possible. Dangerous flash flooding cannot be ruled out over central and eastern VIC and into southern NSW. Thunderstorms will extend back north through western NSW into northeast SA and through much of the NT and into northern WA. The storms may produce dangerous amounts of rainfall in quick time leading to flash flooding. Thunderstorms across the tropics may be gusty at times through the northern tropics into northeast tropical areas as well.

Thunderstorm Forecast Saturday

Thunderstorms will continue over large parts of the nation and now be included into the southwest and west of the nation along a developing heat trough. That marks the potential pattern flip for the west allowing for humidity to return to the region. Over the inland and the east, storms have a high risk of producing flash flooding, which could be dangerous near a tropical low deepening over the NT/WA border near Mulan. The risk of damaging winds with storms over the tropical north remains low to moderate.

Tropical Depression Watch This Weekend

A deepening tropical low within the monsoon trough is likely to lead to heavy rainfall and squally winds to emerge through the areas identified in yellow. Heavy rainfall will spread west through much of northern WA with a flood risk. On the northern flank of the low, a strengthening westerly flow may see showers and storms increase for the northern Top End.

Severe Flash Flood Risk - Friday

The chance of severe flash flooding over parts of Central VIC on Friday is very high with slow moving thunderstorms and a robust and unstable airmass. Thunderstorms may produce high end flash flooding and disruption to major centres and surrounds.

DATA - Refer to the video for further information about the short and medium term breakdown with GFS and to compare with the Euro.

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

The pattern is largely unchanged from yesterday and you should be well versed from the video on book, chapter and verse relating to the different pieces now in the short term that we need to watch. The trough in the southeast drives the severe storm risk with flash flooding, the high humidity over the nation will remain a feature driving the showers and thunderstorms nationally, with the flooding risk increasing for outback areas. The tropics dominated by the monsoonal weather with the trough way south of where it usually is, triggering the heavy rainfall and squalls over interior parts, increasing that flood risk as well. Watching a tropical low through the outlook period over the NT/WA border initially but moving west to sit near Broome bringing heavy rainfall and a flood risk there. Then we have the east coast turning showery, possibly with heavy rainfall thanks to a trough forming mid to late next week.

Euro 12Z - Precipitable Water Values - Next 10 Days

Very heavy moisture content continues with record values across parts of the country, but by next week we could see that very high humidity be shunted north with a new ridge pushing into the Bight leading to a southerly flow. Up north, the monsoonal humidity will take about 10 days to push back to the northern tropics and a drier airmass to move through. The east coast, turning more humid through the middle of next week as the onshore winds develop. That may lead to increased rainfall and thunderstorms coming back to the region which has been sitting under suppressed humid conditions with the ridge nearby.

Euro 12Z - Rainfall Accumulation - Next 10 Days

Refer to video for more information

GFS 12Z - Rainfall Accumulation - Next 10 Days

Refer to video for more information

CMC 12Z - Rainfall Accumulation - Next 10 Days

Refer to video for more information

Euro 12Z - Rainfall Accumulation - Next 15 Days

Refer to video for more information

GFS 12Z - Rainfall Accumulation - Next 16 Days

Refer to video for more information

More weather coming up throughout the day and looking more at the severe weather coverage. The storms will be packing a punch and sadly, I think many who do not use this site, will be quite shocked by the impact.