The weather is largely dry for inland areas this week, with a warmer trend developing, as many centres approach 30C once again. Heat values have come down a tad from weekend projections, but still, well above average temperatures for the inland is expected to continue.
Temperatures will peak over the northern and eastern inland during Wednesday as the front starts to flush out the warm to hot weather over the eastern and northern inland of the nation.
For the east coast, the shower activity today will continue to move north up the QLD coast with a boundary being propelled north by a high shifting through to the east. Some moderate falls were observed over the southeast of QLD and northern NSW and that trend will continue for those areas exposed to the southeast to easterly winds.
Moisture starting to head inland via the southeast to easterly winds, but with relatively stable air over the inland, no rainfall is occurring, but the moisture will head west and then be drawn south and you will see the impact of that moisture being lifted by low pressure mid week over NSW.
The return of easterly winds and moisture deepening over the northern tropics starting to lift the rainfall chances as we go through August as expected. The moisture may turn into productive rainfall soon.
The weekend is interesting, we have that fast moving front that will produce a burst of thundery rain south of the border over NSW. That boundary will move north Thursday but begin to slow down and stall over the border region on Friday, then meander over the southern inland. This will provide the focus for afternoon showers about the region with the chance of one or two storms if the air is unstable enough.
A new ridge this weekend, will bring a burst of southeast to easterly winds again and feed the convergence zone with further moisture. That could add more rainfall chances for the southern inland of the state as well. Showers also expected to redevelop over the coastal areas.
The tropics also becoming unsettled and humid with widespread showers for the FNQ coast and isolated thundery showers over inland areas.
There is more on the medium term moisture impacts in the forecast pinned to the front of the blog home page.
00Z GFS Surface Pressure Pattern for the coming 16 days
The pattern again largely unchanged, the most active area of weather is forecast for the west of the nation for the next 2 days. The east of the nation likely to be warmer than average with that northwest flow. The systems to watch for SA, VIC and NSW is the frontal weather coming through the westerly wind belt during mid this week. Light rainfall and showers for SA and VIC for the most part, not much creeping through the inland. The weather trending back to dry as we go through the latter part of this week. For NSW and QLD keep an eye on the weekend trough as that could see showers become more widespread not only for the coast but for inland areas. Then as you can see some major weather developing for the medium term still likely. That is thanks to multiple inland troughs and that deeper moisture profile.
00z GFS Rainfall for the coming 16 days
The wettest weather is anticipated for mid week still, across SA, VIC and southeast NSW. The weather largely over and done with during later this week. The weather turning dry by the weekend. For eastern coastal areas of NSW and QLD, that trough over the inland could increase shower activity, but those same easterly winds, will bring mild sunny weather for inland and southern/southeast areas. The moisture likely to be pumped well inland via those easterly winds thanks to a strong high over the east this weekend into early next week. We have to keep an eye on the trough coming out of WA next week which may interact with this moisture building over the nation, to produce a more widespread rainfall event, which has been shown multiple times in recent days.
00z GFS Precipitable Water Anomalies next 16 days
The PW values are expected to increase over the eastern states with a plume coming in from the west and another coming through the easterly winds today and tomorrow and drawn south into a front that you can see, lifts that into areas of rainfall. Then another surge of drier air expected to surge through the southern states, but as the modelling suggests, the frontal weather is further south this week, so the dry air stops somewhere over NSW leaving a plume of moisture stuck over the border with QLD. That moisture may deepen further during next week as the trough retrogrades west. High pressure pumping deeper moisture over the north of the nation as well. Another surge coming into WA next week as a trough moves eastwards and that may spread further east during the medium term. By around the 20th there could be a lot of moisture waiting to be lifted by the frontal weather and or troughs.
00z Euro Surface Pressure Pattern for the coming 10 days
The Euro in good agreement with the GFS tonight and other models for the coming 5 days with the frontal weather moving from west to east and linking up with moisture over the southeast while the moisture out of the west thins out over SA. The weekend, watching the upper trough and lingering moisture over the eastern inland of NSW and QLD with onshore winds feeding the trough. Then next week the Euro now starting to come into line with the other models, with showers for the east coast in onshore winds but a trough sharpening over SA and linking up with the longer fetch easterly winds over SA, VIC and NSW to produce more widespread rainfall from mid month. Humid and unsettled over the north from mid month as well.
00z Euro Rainfall for the coming 10 days
Rainfall fairly similar to this morning with the spread settled for the west with the fronts coming through over the coming 24 hours. The rainfall for the east coast also relatively unchanged from this morning with the focus shifting north of Sydney and along the QLD coast as easterly winds increase. The weather then shifts over SA and the eastern inland with that upper trough coming through this time next week with rainfall breaking out. This will continue to chop and change but the model now coming into line with the majority of the global agencies this evening.
00z Euro Precipitable Water Values next 10 days
PW values in line with GFS for the coming 5 days which is good in terms of forecasting the short term, not much shift in the guidance for the system sweeping from west to east and the moisture along the east coast. Where it gets tricky is the upper trough and moisture involvement over QLD during the weekend and whether that seeps south and west and then weather coming in from the west next week, how does that evolve with the moisture, at this time, there is deep moisture available.
Rainfall for the next 10 days
The rainfall along the coast will contract to the northern parts of QLD as the easterly winds become more unstable over the tropics. The airmass is expected to dry out with a northeast to northerly flow developing ahead of that front mid week. That will see the rainfall stay south of the border for now. Another southeasterly surge will bring the showers back during the weekend and the presence of a trough, which is now just being drawn in on the charts, on top of the high, will bring the chance of showers inland if this verifies. It would also increase showers for the east coast as well. But we will know more by Wednesday on that feature.
Tomorrow is climate update Tuesday where I look at September 2021. Also part 2 in the storm series where I look at the flood risk for the nation. Plus a tropical outlook is expected later this week.