A very active period of weather is expected to continue for the east on Friday, with areas of rain clearing the east coast, leaving a clear and sunny start. That is going to allow for a very unstable airmass to give way to showers and thunderstorms, once again these likely turning severe this afternoon.
In the west, a strong cold front is expected to sweep in with rain and storms increasing this afternoon with moderate to heavy falls over the SWLD.
The rest of nation is settled for now, but a fast flow pattern is expected next week with more rainfall potential, lets take a look.
Rainfall for the next 10 days
Rainfall has been heavy overnight in the east and another round of that type of rainfall is likely for areas a little further east through QLD and NSW today. Areas of rain with light to moderate falls for TAS and much of VIC will ease from the west during Friday. Thunderstorms over the southeast will bring the better falls. Rain developing back through SWLD of WA with moderate falls on Friday with that activity expected to move east this weekend, though light and gusty rainfall only for SA and then into VIC and southern NSW Sunday into early next week. For the north the weather turns increasingly humid with showers and thunderstorms about. A better chance of rainfall exists just outside of this period for central and eastern parts of the nation with storms and rain returning. The moisture from the tropics may begin to spark high based showers and storms over inland areas of the NT and QLD, hence the light rainfall placemark to represent this
And when I mentioned uneven distribution of rainfall, this is what I mean. No one can tell you ahead of time, in a random thunderstorm airmass how much you will get, so the above charts are rendered quite useless, so use them as a guide to see where the precipitation is forecast, particularly when thunderstorms are forecast and know you could get double what is shown, especially in the tropics, in the space of an hour.
No change in the spread for thunderstorms across the nation today, the most severe weather expected through NSW and QLD as per yesterday, though the severe thunderstorms will be initiating closer to the GDR and may reach the coast again with some of the storms over eastern VIC possibly turning severe as well. Some gusty storms over northern parts of the NT and over the SWLD of WA, we are seeing another stormy front with a chance of gusty squally rainfall passing through.
Flash Flood Risk
We saw scattered flash flooding reports yesterday with many areas hitting 20-50mm in quick time. This ontop of 20-70mm on Thursday. Similar weather is expected for the east today. 220mm has fallen in parts of the Otways in Victoria.
Large Hail Risk
3-5cm hail was reported from many locations yesterday with those discrete supercells that worked their way through NSW and parts of QLD. That focus shifts northeast today with giant hail also possible up in southeast QLD and northeast NSW.
Damaging Winds Risk
Damaging winds of 90-100kmh reported yesterday with the squall line through the central southern NSW overnight and with discrete cells over parts of QLD and NSW. The potential to pull down the jet stream aloft continues today but mainly over in the north.
A weak isolated tornado is possible today, we saw a few EF0 tornados in western VIC and a couple of stronger tornados through Central and Northern NSW on Thursday. Funnel clouds are likely over southern NSW and northern VIC, some of these could develop into weak tornados. I issued this chart yesterday, not out of entertainment, but as a diagnosis of the atmosphere and these get rarely issued here.
Riverine Flood Risk - Until tomorrow AM.
Flood warnings have started to be issued for some river systems over the southeast of NSW and northeast of VIC. More rainfall about may see other areas go into a minor flood from today if slow moving storms eventuate.
Euro 12z Surface Pressure Pattern and Rainfall Distribution - Next 10 days
The pattern is dynamic and capable of producing high end severe weather over parts of NSW and QLD this afternoon with severe thunderstorms. The weather is expected to turn drier from the west over the coming days as the low pressure begins to open up and move off so by the weekend the weather is back to settled with only a few showers. Over in the west, a strong cold front is likely to pass through with a belt of strong winds and heavy rainfall developing as that system passes through. Some storms could be gusty. The front then collapses as it heads east into the Bight, so only light rain and windy weather coming into SA by Saturday night and Sunday. The system then will bring further light areas of rain and gusty colder winds into southeast Australia next week. Noting the low pressure mid next week over SA through the east may bring better rainfall odds, the models continue to show this trend, so the most widespread rainfall for the south and east will be mid to late next week and much of the interior should be hot and become more humid. There are hints of storms returning to QLD and the interior of the NT by the end of next week.
Euro 12z Precipitable Water Anomalies - Next 10 days
No real change from yesterday, the high PW anomalies still remain in place over the southeast and east of the nation with heavy precipitation and thunderstorms as a result. The weather will then turn more seasonal nationally with drier air coming back into the mix, though moisture will begin to recycle through northern Australia and be drawn southeast into the mid latitude westerly winds, lifting rainfall chances and the chance of thunderstorms over parts of southern and eastern Australia as troughs and fronts move through. Heavier moisture levels start to build at the end of the run leading into another rainfall event for the nation into the second week of October, this appears to be around the WA region and back over the tropics and eastern QLD.
Euro 12z Rainfall Accumulation - Next 10 days
A lot of this to come down in the next 24hrs over in the east. Rainfall comes back through the west from this morning with heavy falls possible with thunderstorms. There will be scattered showers about the southern coast of SA and into the southeast states as the front weakens and moves over with patchy falls into next week, some of that may extend inland into NSW. A more robust system mid to late week as mentioned in the video could bring widespread falls back into the southeast and eastern inland. Otherwise the weather over the eastern inland dries out fairly efficiently this weekend into next week under a ridge. Watching that moisture over northern Australia with some chance that may take a trip down the Stuart Highway and be drawn through to the southeast and east of the nation. We will wait and see.
GFS 12Z - Rainfall next 10 days
Check out the blog video for more details
Severe weather updates to continue this morning and medium term forecast mid morning and a look at the medium term forecast and the harvest outlook by lunchtime.