Finally, some summer like temperatures are on the way for the southeast and east of the nation with a high pressure ridge moving to the south of the nation, but it is moving slowly, so skies have cleared nicely for the past 5 days allowing the air to heat up. The warmer weather is expected to move eastwards into SA over the weekend into early next week and then into VIC and western NSW.
In the east of NSW and QLD, the heat won't quite make it towards the GDR with onshore winds and a trough in the region producing cloud, showers and storms with further heavy rainfall possible.
The tropics are set to see an increase in wet weather during the coming week with locally heavy rainfall become more scattered in nature. The moisture from the tropics will start to creep southwards as the high drops further south of the nation allowing for a large scale easterly flow to establish.
Lets take a look at the latest details.
The moisture has contracted east now and the majority of the nation is quiet with clear skies and a mild to warm easterly wind which is tending hot over in WA and western and northern SA. The showers and thunderstorms will likely continue for the eastern third of the nation today with heavy falls confined to QLD and northeast NSW where storms form. Overnight we have seen thunderstorms producing significant and dangerous flash flooding and riverine flooding is well and truly underway through much of northeast VIC, NSW, parts of the ACT and QLD. The warmer drier days will be welcome for many areas over the coming 2-3 days with the high dominating. Where you see the cloud cover today is where it will be over the next 2-3 days before moisture spreads the rainfall back west through the east.
Rainfall Next 7 Days - November 27-December 4 2021
Rainfall has largely contracted as expected to the east and over the north of the country with the trough and low responsible for the wild weather weakening but lingering over the east this weekend. The trough will move back west through NSW and QLD during early next week taking the thunderstorm focus back to interior parts of both states. The moisture will likely deepen once again throughout NSW and QLD bringing more widespread showers and thunderstorms for much of the east mid week ahead of a weak trough that will sweep through during mid to late week over the southeast of the nation. The majority of SA, WA and the interior parts of the NT remaining dry for now. It is becoming clearer that the moisture and showery/stormy weather will likely continue into the medium term.
Rainfall Following 7 Days - December 5-12 2021
The persistent easterly flow and the presence of troughs in the east are expected to bring widespread showers and thunderstorms to the east, and another trough over the west with scattered showers and thunderstorms redeveloping in response to moisture running down the west coast. The weather over the north becoming much wetter and thundery and that moisture will creep south with the coverage of rainfall becoming more widespread across the nation.
Thunderstorm Forecast Saturday
Thunderstorms are likely about the eastern portions of QLD and extend into northern NSW during the afternoon and evening as a trough becomes near stationary from today and begins its journey back to the west. On and east of the trough is where you will find thunderstorms which may turn severe with heavy rainfall leading to flash flooding. Over the north, routine afternoon and evening showers and thunderstorms, some of those gusty and heavy as per recent days and seasonal expectations coming into December.
Thunderstorm Forecast Sunday
The trough in the east is expected to move west to be over central and northern NSW and extend through southern and central inland QLD and wrap into the northern tropics. Widespread showers and thunderstorms developing along and to the east of this trough with severe thunderstorms possible. Heavy rainfall leading to flash flooding is the main risk along with damaging winds. The storms over the northern tropics could also be gusty.
Thunderstorm Forecast Monday
The trough remains near stationary on Monday but could extend to southern inland NSW during the afternoon with scattered showers and thunderstorms from about the ACT north along and to the east of the trough through NSW and QLD wrapping back into the tropics. Heavy rainfall may lead to flash flooding once again over the eastern inland of NSW and QLD.
12Z Euro - Surface Pressure Pattern and Rainfall Next 10 Days
The pattern is relaxing a bit after a busy week, with the majority of the nation under a ridge and easterly winds so mild to warm weather developing for much of southern Australia and hot weather continuing for WA. The heat will spread east this week as the ridge moves east. But that same ridge is pumping onshore easterly winds into QLD and NSW which will feed troughs and lead to further showers and thunderstorms throughout this coming week, no chance to dry out, but the coverage of rainfall at least is less extensive. The tropics having a noisy morning over the NT and QLD, with this activity expected to continue for the coming week. The only blip on the radar for the southern parts of the nation will be the high establishing once again to the south of the nation, allowing a weak trough to move through bringing milder weather from later this week which could spice up the storm activity later this week over NSW and QLD. That reset in the high pressure is what will lead to heavy rainfall developing for the east coast of NSW and QLD during December.
12Z Euro- Precipitable Water Values - Next 10 Days
The moisture content is remaining high over QLD and NSW through this period where the drier air has now settled in over VIC, SA and WA with high pressure slowly moving through the region. The moisture via easterly winds can be seen creeping west over the eastern inland and combining with the troughs to keep the tropical feel in the weather going. The north of the nation is where you find the deep moisture as well, and that starts to creep south and west bringing up the chances of rainfall as we move through the first week of December. The deepest moisture is limited to the east and north of the nation through this period before the moisture covers the nation as the high to the south drifts further south promoting the broad easterly wind regime.
12Z Euro - Rainfall Accumulation - Next 10 Days
Rainfall as mentioned has now contracted to eastern and northern parts of the nation as the prevailing wind direction with a new ridge moves east through southern waters. This pattern will remain largely unchanged for the best part of the next 10-14 days under the positive SAM. While there is the absence of a major rainfall event for inland areas, one can pop up in this environment at any time and where this would be more likely to develop would be over the eastern inland of Australia. For now the heaviest rainfall is over the eastern inland of NSW and QLD and into the tropics. A weak thundery change may develop for VIC later Wednesday bringing hit and miss showers and storms, some chance of the moisture building over SA and the interior later in the run but I am not convinced of that. The remainder quiet and dry.
12Z GFS - Rainfall Accumulation - Next 16 Days
Note the heavier rainfall connected to the easterly winds and developing trough once the high to the south redevelops and resets its position, promoting that deeper moisture passing into the eastern inland. The west may remain fine and sunny for now but the moisture will start to increase towards the end fo the period and that signals a wetter shift for the nation as we head into mid December
CFS - Rainfall Next 6 Weeks
Remaining very wet through early next week.
I will have another update at some stage this evening, but with the weather taking a breather, I can take a breather for a moment after a busy 3 weeks. Have a great Saturday.