And so are the heavy rainfall totals. The flood potential is running high this week as mentioned and the severe thunderstorm risk is expected to become more widespread from today over northern and western parts of the nation. The east may see a reduction in the severe thunderstorm activity today, will watch trends closely.

The rain and thunderstorms are expected to increase over the eastern inland tomorrow with a trough and low over the southeast invigorating the upper atmosphere and lifting the humid air into an organised batch of showers and storms which will likely turn severe through NSW and QLD. All modes of severe weather possible including large hail.

At the same time, we have a deep surface low and significant rainfall and thunderstorms passing through the central parts of the nation with heavy falls. Outback flooding is likely mid week.

Then that low sweeps into VIC, NSW and QLD with further heavy rainfall with a flood risk developing later this week. Some locations could see 150mm of rainfall from this event on top of what will fall between now and then.

A low deepens off the southeast coast with rain focussing over the southeast of NSW while cooler drier air surges north throughout the nation, sweeping the humidity out and lowering the rainfall chances.

The cold and wet, windy weather will be an issue for graziers, especially stock that has been sheared over the southeast. In the west, by contrast, the west is warm....finally.

Lets take a look.


Rainfall Next 10 Days

The passage of a low pressure system over WA through SA and then into the eastern states offers the most widespread rainfall, but the system emerging from tomorrow also carries a significant rainfall event ahead of that system in WA over QLD, NSW and VIC with deep moisture being worked over once again. Heavy rainfall is expected to develop in response to this trough rotating through during Wednesday, especially through QLD and NSW. At the same time, a low pressure system over the southwest of the nation is expected to move into SA sparking rain and storms with heavy falls for parts of SA and the NT. Then this feature moves east and brings follow up heavy rainfall into QLD, NSW and VIC from Thursday afternoon and clears by about Saturday with a drier and more stable airmass moving through western areas from mid week, reaching the east by this weekend. But by the weekend, we could be dealing with many rivers in flood to take us through next week. A few drier days can be expected next week but humidity is appearing to return much more quickly with showers and storms creeping south from the tropics once again.

Thunderstorm Forecast Tuesday

Thunderstorms are expected to bring severe weather to parts of the eastern inland of WA and extend into SA during the afternoon and evening. Thunderstorms are also expected into the NT with those turning severe over the western and southern districts. Storms may also be gusty at times over the Top End. Storms over the eastern portions of NSW and QLD may bring heavy rainfall leading to pockets of flash flooding, but it is more likely over QLD tomorrow. Thunderstorms may produce damaging winds and gusty winds over Central inland parts of QLD.


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

The dynamic and energetic weather pattern with amounts of atmospheric moisture is expected to continue for the coming 4 days before we have a pattern flip, colder drier air surging through nation from west to east mid week clearing the skies and bringing a reduction in rainfall for a number of days into next week. The tropics will keep the moisture with showers and thunderstorms right throughout the period, but that moisture is likely to creep south once again this time next week and feed troughs setting up over the nation's west and east.

12z Euro - Precipitable Water Anomalies - Next 10 Days

Deep moisture layer streaming in from the northwest to the southeast will continue to bring heavy rainfall and thunderstorms. But note the shades of brown coming in on the backside of the deep low as it traverses the nation. That will bring a pattern flip and colder weather for much of the nation with a gusty southerly. The moisture retreats to the north and northeast but creeps south again, and will be taking a look at the medium term later today, but watch the Indian Ocean influence, with more moisture surging southeast again.

12z Euro - Precipitable Water Values - Next 10 Days

The values are near record for the NT and QLD and that extends into northern NSW as well during the latter part of the week, and with the low pressure rotating through this airmass, high end rainfall and flooding is a significant risk. But then conditions settle down as we see moisture levels return to normal to below normal values behind the low pressure system thanks to southerly winds and a ridge building over the nation.

12z Euro - Rainfall Accumulation - Next 10 Days

More information on these can be found in the video but note the difference from model to model. I will point out once again with the low diving southeast through NSW and eastern VIC and the trough snapping north through NSW into QLD and the NT, some locations in eastern SA and central NSW may miss out on rainfall advertised as that area where the systems diverge will sit in dead air with limited rainfall opportunity. So a few places could see a bust forecast.

12z CMC - Rainfall Accumulation - Next 10 Days

12z GFS - Rainfall Accumulation - Next 10 Days

More details on the harvest outlook coming up after 10am.