The dynamic and unstable weather pattern continues for a large portion of the nation coming up this week, with rounds of troughs digging into deep layer moisture resulting in widespread showers and thunderstorms, some of which likely to be severe. The threat of more organised rain events are too present through this time for much of interior Australia.

Impacts could be felt in areas that have not seen much rainfall so far this Summer. As is the theme with La Nina patterns, it is all at once or nothing at all for the central parts of the nation. I think many areas are going to see exceptional rainfall over the coming 2-3 weeks and now is the time to prepare for the worst but hope for the best.

For our friends in the southwest of the nation, things look fairly quiet for now, but that tropical system up north may be a game changer. If it does decide to pass further west through WA rather than go through the NT, then we may see more rainfall come back for Agricultural areas of WA with the risk of flooding.

In eastern Australia, there won't be much break from the humidity and you will be joining the northern tropics with above average humidity and rainfall chances for the period ahead.

Lets take a look


Rainfall Next 10 Days

This continues to be a very tricky element to forecast well, ahead of time. With the major weather events still hard to pin down, this means your number will vary from update to update. This means significant rainfall for some with flooding in one run, is replaced with regular rainfall expectations from SA, through the NT into QLD, NSW and VIC. So be aware of all that lovely app data you are looking at this morning. The weather dominated by a deep moisture profile over the nation's interior. The other component is the deep trough over SA which moves very slowly eastwards over the weekend into next week with significant rain and thunderstorms moving eastwards. Riverine and flash flooding is of concern for SA and possibly extending into NSW and VIC later in the weekend into next week. A tropical low over the north of the nation embedded within the monsoon trough will descend southwards, with the chance of heavier rainfall developing for coastal areas and this shifting southwards throughout next week and beyond Australia Day. That moisture will then feed into the weather already in place over QLD, NSW and SA, maybe as far southeast as VIC. So further rainfall beyond this period is highly likely. SWLD of WA remains dry.

Thunderstorm Forecast Tuesday

Thunderstorms will continue in a broad risk across the northern and eastern parts of the nation with severe thunderstorms possible with heavy rainfall in a band from the NT through northern SA into western and central QLD and NSW. Dangerous flash flooding is possible through northeast SA and southwest QLD. Storms may be severe over the NT with damaging winds as well. The west coast of WA may also see a few showers and thunderstorms but severe weather is unlikely.

Thunderstorm Forecast Wednesday

Thunderstorms will continue along and to the east of a trough through the NT, stretching through QLD and into NSW with the remnants of Tiffany leading to deep moisture levels and the chance of heavy rainfall leading to flash flooding. Up north, the risk of damaging winds is possible in the NT and through outback areas. High based storms possible about a seabreeze front during Wednesday afternoon in the northwest of WA.

Thunderstorm Forecast Thursday

Thunderstorms are expected to continue through the central interior and through to the eastern inland in a moist and unstable airmass. Heavy rainfall from thunderstorms could lead to flash flooding in the Central NT and through western QLD and eastern WA. Thunderstorms may also develop along a new trough sharpening through central SA through to the Agricultural areas, with gusty winds and moderate rainfall.

Tropical Depression Watch - January 20th-27th 2022

Tropical depression may form as early as Thursday up over northern parts of the Arafura Sea and track southwards. The upper level winds and SSTs are favourable for development into a cyclone, but it needs to stay over water and avoid the island chains north of the nation. One way or the other, enhanced rainfall later this week over northern Australia is likely with a developing low off the Kimberly Coast by the weekend.

Severe Thunderstorm Risk - January 22nd-27th 2022

A deep trough over the central parts of SA is expected to form during Friday and across the weekend, deepening further, pulling in high levels of moisture with the risk of severe thunderstorms over a number of days. Storms will carry the risk of heavy rainfall leading to flash flooding and damaging winds. Hail is a very low risk. Thunderstorms will progress towards the east during the weekend and over the course of next week and Australia Day.

DATA - Refer to video for more information where I look at GFS.

12z Euro - Surface Pressure Pattern and Rainfall Distribution - Next 16 Days

No real change to the guidance from overnight from the Euro, still showing the moisture and thundery weather in the east moving offshore, but part of that moisture hangs back and heads west, being fed into the new upper trough over SA by later this week, leading to a major storm outbreak with heavy rainfall possible for central and eastern SA. The stormy weather however is looking like it may struggle to sweep into VIC, NSW and QLD on some of the guidance so will keep watching trends, but it is looking humid and unsettled none the less for NSW and QLD for the period, regardless of what happens with the upper trough. Showery weather for the east coast in onshore easterly winds. Up north the monsoonal flow and a tropical low may develop later this week and then sweep southwards towards the northern parts of the nation. That moisture may come south into the nation and a westerly flow will bring more rainfall for the NT and QLD. The tropical low may bring heavier rainfall to northern and northwest WA. Fine weather over the southwest of the nation with a drier airmass and high pressure.

12z Euro - Precipitable Water Values - Next 16 Days

No change to the moisture distribution across the country through the coming 10 days. Significant moisture is expected to remain in place for northern and eastern parts of the nation. With low pressure and warm temperatures, this will result in the very tropical weather to continue for the next 10 days. The dry weather is expected to continue for the southwest of the nation and that drier air may come through to the east and southeast of the nation if we can get a push of westerly winds after Australia Day, but that remains to be seen. Finally the tropical low that is forecast to form looks to adopt a more westerly track through into the Indian Ocean, but it will skirt close to the NT and northern WA coast this weekend, this low will help to bring in the monsoonal flow.

12z Euro - Rainfall Accumulation Next 10 Days

Refer to video for more information

12z CMC - Rainfall Accumulation Next 10 Days

Refer to video for more information

12z GFS - Rainfall Accumulation Next 10 Days

Refer to video for more information

12z Euro- Rainfall Accumulation Next 15 Days

Refer to video for more information

12z GFS - Rainfall Accumulation Next 16 Days

Refer to video for more information

Your latest 6 week outlook comes out today plus looking at the La Nina in greater detail to see how we are tracking. And a look at the severe weather potential for the north and central parts of the country as well.