Showers and thunderstorms are expected to develop from the west during Wednesday with a trough finally moving from the west through WA and into SA, starting to lift that really humid air above our heads leading to widespread rainfall developing.
The showers and thunderstorms are expected to pass through the state, mainly west of the divide as we get into the end of the week with moderate to heavy falls possible with thunderstorms.
Along the east coast, onshore winds keeping the region stable, though the humid air is being pumped inland into the trough of low pressure over inland regions, so while it may be cooler and showery along parts of the coast, the weather over the inland is expected to be active, bringing more downpours and gusty conditions.
More stormy weather is expected next week with a series of troughs and deep moisture to continue.
Lets take a look
Rainfall Next 10 Days
Rainfall is expected to be fairly scattered, uneven in distribution with a deep and warm atmosphere leading to showers and thunderstorms in random locations from day to day. Now in saying that, most areas will likely pick up a decent storm through this period and many of you should see at least 1/2 month worth of rainfall with this first trough. More showers and storms are expected right through the weekend and next week with moderate to heavy falls with thunderstorms. The coastal areas will see showers increasing during the weekend into next week as the onshore northeast to easterly flow turns more unstable so the rainfall becoming more widespread as we go, but again, your number will vary from day to day.
Thunderstorm Forecast Wednesday
Thunderstorms with gusty winds and heavy rainfall over parts of the NT and SA this evening will move into the southwest and far west tonight and continue to move eastwards, slowly, during Wednesday. Further severe thunderstorms with gusty winds and heavy rainfall is possible about the Warrego during the afternoon and evening, these thunderstorms are expected to be moving south or southeast.
Euro 00z - Surface Pressure Pattern and Rainfall Distribution - Next 10 Days
The pressure pattern is largely unchanged from this morning and I will point out that this is the more conservative approach to the short and medium term, and yet there are still severe weather events and heavy rainfall for many parts of the nation. Your number will vary as you track through the next few days. I will reaffirm the issue in forecasting rainfall and temperatures in this environment is very tricky. Now we have one trough moving through now into the end of the week, that gets stuck over the southeast and eastern inland. The next trough emerges out of WA through Friday and moves eastwards and drives more showers and storms from SA through to the eastern inland of the nation over the weekend and next week. A third feature is the one causing the most interest, now the Euro has had it in recent runs like the GFS, an upper low over WA moves into the moist and unstable air trapped over the eastern inland forms a potential severe weather event right at the end of the run into the medium term. This carries low confidence and there is no skill in being specific other than mentioning it in the way I have. The northern tropics unsettled and humid and the southwest of the nation mostly dry until we see that potential upper level system at the end of the run.
Euro 00z - Precipitable Water Anomalies - Next 10 Days
Deep moisture is now moving through SA and into VIC and NSW, you may have noticed the afternoon cumulus in the east under the warmer layer at about 10000ft, that is indicating the low level moisture is increasing and tomorrow the whole of the south and east will feel very tropical. This tropical air is set to stick around for much of the nation away from the tropics for most of this outlook period. It will spawn rain and thunderstorms for many areas with heavy falls in random scattered pockets in multiple states. The drier air seems to be trapped over the SWLD with onshore southerly winds and the upper ridge keeping things calm until about day 9-10. For now this weather coming through in the next week is unusual in terms of the scale and depth of the moisture this early in the season.
Euro 00z - Precipitable Water Values - Next 10 Days
The hotter the colour, the more moisture to work with and there is plenty on the board. There is a mixed bag in the period next week with models unsure how to handle the moisture to the north, does it come south of is it kept north over QLD, NT and WA thanks to ridging? We have to wait and see, but in the short term, it is soupy for most of the country. GFS in the video shows you when the moisture escapes south into colder air aloft, this scenario shows you the ridge holding firm and keeping the moisture and wet weather further north. We simply have no way of knowing if this will occur this far out, there are too many moving pieces ahead of it.
Euro 00z - Rainfall Accumulation - Next 10 Days
More details in the video.
A closer look in
GFS 00z - Rainfall Accumulation - Next 16 Days
More details in the video. This is IF the upper low heads south in the medium term and again this remains low and I suspect that the model will change overnight. But southern QLD should be watching closely.
More details coming up tonight with a look at the full model spread on the rainfall outlook, as many people are looking at that most of all.