The storms over the northern Top End finally brought a period of cooler weather to northern communities, including Darwin this morning. Point Stuart recording 100mm of rainfall overnight so certainly some very heavy November rainfall continues for pockets.
The rainfall is expected to remain uneven in distribution with the showers and thunderstorms, however the rainfall will become more extensive as the moisture continues to deepen and troughs converge throughout the NT, leading to more productive early season rainfall.
Lets take a look
Rainfall Next 10 Days
As mentioned throughout the past few weeks, uneven rainfall distribution continues but the coverage of rainfall is becoming more widespread as we see the moisture deepen and troughs converge throughout the NT. Some of the rainfall could be heavy at times, some outback towns could not only exceed the average but break November rain records through this period. There is no clearance of the moisture and rainfall from the NT during this period, so settle into a tropical week NT wide.
A broader outlook across the NT shows the heavier rainfall west of the Stuart Highway in the coming week. Also the heavier rainfall will contract eventually to the Top End.
Thunderstorm Forecast Wednesday
Thunderstorms are expected nearly NT wide on Wednesday with the more likely areas of thunderstorms expected over the Top End and down the Stuart Highway, to the SA border. Storms may be gusty and heavy at times with pockets of flash flooding and squalls to 100km/h. The wind issues may be closer to the SA border.
A broader look at the thunderstorm risk across the NT.
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.
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.