A little unsettled about the southeast inland, Cape York and the Gulf Country. The instability was a little more robust than expected today with severe thunderstorms ongoing this evening. The increase in humidity with showers with thunder will feature daily throughout the outlook period, becoming more widespread as we track into the weekend and next week.
Multiple waves of low pressure is expected to pass through from the Central interior and then towards the eastern inland from later this weekend.
Some of the storms are expected to be strong to severe over southern and southeast areas of the state on Sunday with locally heavy rainfall the main concern and this is limited to where the low pressure system does moves.
A new wave of low pressure from mid next week offers a better chance of widespread showers and thunderstorms with moderate to heavy falls possible for southern and central districts then moving onto the coastal areas.
Also into the medium term, watching tropical waves to the east on the approach, this could bring widespread rainfall to the east.
Lets take a look
Rainfall Next 10 Days
Rainfall is light to begin with, the showers along the coast and thunderstorms that get up through a strong cap is expected to be generally isolated and short lived tomorrow and Friday. But as we get into the weekend, the air aloft becomes colder and the air more saturated, the rainfall coverage increases dramatically for southern areas on the weekend into early next week. A better placed and organised system is expected to approach from the west mid next week, with areas of rain and thunderstorms possible. The wet signal is expected to increase during next week and to the end the month with strong signals for coastal rainfall to trend above average.
Thunderstorm Forecast Thursday
Thunderstorms are expected to develop over the same areas but unlike today, unlikely to be severe at this time. Overall, the risk is low for severe weather but as always, QLD in Spring and Summer with thunderstorms, expect the unexpected.
DATA - Refer to the video to see CMC and the comparison
00Z GFS - Surface Pressure Pattern and Rainfall Distribution - Next 10 Days
The GFS has moved further into line with the CMC which I believe has been handling this first system best. We have a junk type system passing through WA into SA then VIC and TAS Thursday and Friday with patchy rain and thunder possible. Moisture is limited as mentioned. Showers return to the tropics with thunderstorms about. Isolated strong storms possible through southeast QLD and northeast NSW inland of the coast Thursday. Areas of rain likely to increase over the southeast of WA and enter SA through Friday into the weekend with the more dynamic system moving through. The system reaches VIC and NSW Saturday and moves east of these states during Sunday. Rainfall heavy at times over the southeast with this feature which maty renew flooding. There may be strong to severe storms in the warmer sector north and east of this feature over the remainder of NSW and southern QLD Sunday. Then conditions clear for early next week in these regions. Thunderstorms increasing over the tropics from the weekend through next week with that moisture surging south into QLD and the southern NT and this may be captured by a follow up trough which, if it develops, could spread rain and thunderstorms throughout the southeast and eastern inland of the nation once again. The west turning warmer and drier throughout this period with the wet weather over the east of the nation.
00Z GFS - Precipitable Water Anomalies - Next 10 Days
Humidity is on the rise as mentioned throughout this period. The monsoonal flow is about 4-5 weeks away from northern Australia and once that increases over the north of the nation, the weather will turn even more humid and wet across the nation. The drier days will be hard to find. While you may not see a lot of green on this chart, the tropics are soupy to start with so if you see greens and blues up there, that is a huge issue for those not wanting severe weather, rainfall or humidity to extend across the nation. This run of GFS is a lot drier than the ensemble data set that I have seen throughout the day.
00Z GFS - Precipitable Water Values - Next 10 Days
With the system passing through the nation in the short term, it will be tapping into PW values of 30-50mm across SA through NSW and VIC which will lead to extensive rain and thunderstorm activity. The thunderstorm coverage will be more active in the regions that can break through to the low 30s this weekend. The deep moisture profile remains in place until the end of the period over northern Australia and especially through the Coral Sea and Indian Ocean but note the mobility of moisture over the Coral Sea and its advance towards the east coast of QLD and through the tropical north.
00Z GFS - Rainfall Accumulation - Next 10 Days
Refer to video for more
00Z CMC - Rainfall Accumulation - Next 10 Days
Refer to video for more
I will have more on all things rainfall and modelling coming up after 9pm EDT tonight.