The latest details on the next 6 weeks taking us through to the end of Summer is below. There is very little change on the data sets for the coming 6 weeks, however the short term forecast could provide some very heavy rainfall for interior parts of the nation, especially from the eastern parts of WA through the NT into northern SA then onto the east with heavy falls about for NSW and QLD.
The rainfall to come for the remainder of January looks heaviest for the east and the north of the nation with further troughing and deep moisture in place. The southeast may see a little break with ridging passing through. For the west of the nation, the wild card for January is the secondary cyclone that is expected to form over the Indian Ocean in the medium term.
The monsoon is expected to strengthen through the remainder of the month over the north, that will lead to a cooling of the very hot nation in the coming 2 weeks and a cooler and wetter February for large areas of the nation is likely.
February, bottom line looks wet and cooler for many areas with episodic flooding for the north, interior and eastern portions of the nation.
As we move into March, the humid and unsettled weather will continue, especially for eastern Australia, as we track into the wet season for the eastern seaboard.
Rainfall Outlook - Next 6 Weeks - January 14th - February 28th 2022
% chance of exceeding the median rainfall for the coming 6 weeks
The wet signal is expected to peak in the coming 6 weeks with the La Nina peaking within the coming fortnight. This wet signal will focus over interior parts in line with the monsoonal burst developing over northern Australia, persistent easterly winds over eastern Australia and the positive SAM phase keeping the high pressure systems further south. This will promote that humid and unsettled pattern to continue, which what we have experienced this week. The models are very wet for interior parts in the short term and once again in the longer term. The east looks persistently wet and rainfall will increase for SA gradually over the course of the next fortnight and return once again during February. For WA - watch the tropical activity in the coming week over the far north, that may bring rainfall and relief to interior parts of the state following the high heat, very common to see a cyclone run over the areas that have been baking. That may also help drag in a monsoon through the nation's north.
Temperature Outlook Next 6 Weeks - January 14th - February 28th
% chance of exceeding the median temperatures for the coming 6 weeks
We are seeing the blues taking over the board now with a lot of the higher heat we have observed in recent days now behind us and more cloud and rainfall likely to emerge in the coming weeks than the clearer skies. This will lead to below average temperatures, not cold, but the more humid weather will bring those temperatures over interior parts in conjunction with cloud cover and rainfall. With La Nina peaking in the coming weeks, this will not be felt until February onwards, where the rainfall peaks in intensity and frequency over eastern and northern Australia in particular. Finally, a protracted monsoonal flow is forecast through late January or into February.
Humidity Outlook - Next 6 Weeks - - January 18th - February 28th 2022
% chance of exceeding the median humidity for the coming 6 weeks
High levels of atmospheric humidity is expected to remain in place for the coming 4 weeks at least with only weather signals for a pattern shift over southern areas during later January into early February. At this time, the absence of southern westerly winds, will mean that the weather is expected to remain very humid and soupy for much of the interior, we have experienced that in recent weeks and will see that expand across the central and western interior through this period with rainfall chances to increase in line with that.
Disease Outlook - Next 6 Weeks - January 18th - February 28th
The persistent high humidity and warm wet weather brings about high to major brown rot risks to the food bowl in the east - this could also extend further west and northwest in the next update. But this forecast has verified very well so far this season.
Riverine Flood Risk Summer 2021/22
The flood risk is ongoing and continues through the remainder of January into February, and with the wet signal looks to peak in February. The weather has certainly thrown out some high end flash flooding events this week and that is a taste of what is to come for the next 6 weeks. All parts of the nation bar the far southwest of the nation has some degree of risk for the remainder of Summer.
CLIMATE DASHBOARD - Next Update Tuesday 18th 2022
A very wet signal across the main drivers, the ENSO and SAM continues to drive the wet weather for the north and east of the nation. The heaviest of the rainfall is being felt at the moment through eastern and northern Australia, which has been the pattern for a while now. The SAM is expected to turn neutral later in the weekend and into early next week but it will tend positive once again, the southern parts of the nation should not see too much change to what we have experienced so far. For the north of the nation, the below drivers are supportive of seasonal to above seasonal rainfall and seasonal temperatures. The MJO is expected to roll into phase across Australia by the end of the month and the first half of February seeing the rainfall increase to very high levels, that will play out across the nation with a deeper moisture profile, this is on top of what has already been forecast in the short term. For SA and WA, the southern areas will remain dry for a while, there will be the odd shower or storm over the coming 10 days and hot temperatures, but the rainfall should begin to increase and the temperatures decrease as we move through this period as moisture from the north begins to creep southwards.
TROPICAL WEATHER - Next Update Tuesday 18th 2022
January 8th-Febraury 7th 2022
The MJO is expected to move into the Western Hemisphere with the break conditions experienced over recent days expected to conclude from east to wet across the nation's north. The tropical wave spoken of last week formed into TC Tiffany and that is now in the Gulf. The system expected to move west and continue to dump tremendous rainfall this week and possibly allowing a pseudo monsoon to develop with further rainfall beyond this week. That deep tropical moisture will likely drift towards the Kimberly and become slow moving and subtropics into the second half of the month. Looking at the MJO, it may begin to emerge and move towards Australia by the end of the month, however some members below want to bring the MJO back into the north by as early as next week. The general rule is for it to emerge in the Indian Ocean during early February but I reckon that is a little slow.
SOUTHERN ANNULAR MODE
January 14th-31st 2022
The positive SAM phase is peaking today and tomorrow before it plummets back to neutral conditions by the weekend into early next week, this allowing the moisture to be propelled northwards thanks to a high ridging further north than the past fortnight. This will also disrupt the flow of tropical moisture streaming out of the north and northwest leading to less rainfall for a period over southeast Australia. The SAM is expected to turn positive again for the end of the month which will lead to extensive rainfall and humidity developing again over the north and east of the nation. With the shift in the SAM next week, it will allow for moisture to stream southeast and south through the nation from the tropics.
Euro Rainfall Accumulation Ensemble Data - Next 6 Weeks - January 14th - February 28th
No change to the signal with additional heavy rainfall for the north and east of the nation but note the rainfall is spreading southwards through SA and WA with troughs helping to drag the moisture southwards, that is thanks to the remains of Tiffany. Showers and storms will return to those areas that have turned dry in recent weeks if not month and the potential of heavy rainfall is likely, but this will be repeated multiple times over the course of the next 6 weeks Further tropical lows and the monsoon will see a very wet spell for northern Australia over the next 3-4 weeks. The east, very wet with a heightened flood risk in place for QLD, NSW/ACT and VIC.
Euro Rainfall Accumulation Control Data - Next 6 Weeks - January 14th - February 28th
Very heavy rainfall in the short term with the remains of Tiffany will dominate the nation's rainfall and moisture supply. The positioning of high pressure with the SAM returning neutral next week will keep the moisture at bay for the short term but it will come south for the end of January and February is looking wet nationally.
Euro Rainfall Anomalies - Next 6 Weeks - January 14th - February 28th
This is probably closer to the post and finally showing the monsoon and tropical low impacts over northern Australia and this beginning to spill southwards over the remainder of the nation. The west of the nation will see further rainfall and SA you should also see rainfall return into February. I am of the belief that the eastern portions of QLD will be wetter than what is being advertised.
GFS Rainfall Accumulation - Next 5 Weeks - January 14th - February 16th
There are signals for heavier rainfall over the north of the nation and the return of a full monsoonal burst. The east wet under persistent easterly winds and troughs nearby. The interior also wet in response to moisture pooling and being lifted by inland troughs. The SWLD of WA may see further rainfall than what is advertised here.
GFS Rainfall Anomalies - Next 5 Weeks - January 14th - February 16th
This is showing you how off the ball GFS is with regards to rainfall over northern Australia which means that most of the nation's weather is of low confidence regarding rainfall.
CMC Rainfall Accumulation - Next 4 Weeks - January 14th - February 7th
Extensive moisture being transported south and east through the interior of the nation with heavy falls and flooding. Additional heavy rainfall expected over northern and eastern Australia with additional flood risks. The driest part of the nation looks to be the SWLD of WA but not even there will be dry.
CMC Rainfall Anomalies - Next 5 Weeks - January 14th - February 7th
Impressive and near record rainfall anomalies are expected to continue throughout the northern and central interior, with flood risks likely to increase through this period. The pattern flip allows the troughs and moisture to move further west away from NSW and QLD, but that doesn't mean these areas will be drier by any stretch of the imagination. Even SWLD of WA looking wet but the big shift will be through SA.
Euro Temperature Anomalies - Next 6 Weeks - January 14th - February 28th
This is probably closer to the post, with the west and south drier and warmer, the east and north, cooler and wetter which is La Nina 101. You can see the influence of the monsoon over the north and curiously perhaps moisture and more cloud coming through WA and into SA towards the end of the month and early February.
GFS Temperature Anomalies - Next 5 Weeks - January 14th - February 16th
This model has been running too warm but it is not impossible given the stagnant pressure pattern across the and the absence of the monsoon over the north, however the GFS does not see the tropical low over the north to cool the interior down, so in the absence of tropical weather the nation would warm up.
A refresher on what happens following La Nina...
This is the preliminary look at the guidance.
% chance of exceeding the median Autumn Rainfall 2022
The chance of exceeding the median seasonal rainfall is remaining elevated over portions of northern and eastern Australia as a direct result of the La Nina waning through the March and possibly lingering into April. It is something to watch as we move through January. If this was to occur, the result would be even wetter weather for the north of Australia with a prolonged wet season, the eastern seaboard will be very wet (especially if the SAM remains positive) and the wet season along the NSW coast which runs from March until June would be equal to what we saw earlier this year, producing those high end floods. The risk is near similar to last year. For the southeast and south, near normal conditions for the season is expected. The beginning of Autumn would likely start out wet but potentially turn more seasonal as we go along. No dry bias is currently strong enough to be drawn onto the charts at this time, but if there was to be a drier location, it would be SA and southern parts of WA. There is no signal for a negative IOD to develop through Autumn at this time however, it is not expected to be anything other than neutral. Conditions remaining seasonal in terms of influence from the Indian Ocean. The Autumn break may not be required, in fact it could be an Autumn break from the rain that we need!
% chance of exceeding the median Autumn Temperatures 2022
Temperatures mostly seasonal throughout though leaning cooler over the east and north. This would be linked to the persistent cloud cover and widespread rainfall developing throughout the nation's north and east and the wet season in both locations to be above normal. The rest of the nation likely to see normal conditions overall with the usual fluctuations in temperature. The guidance still not great this far out to measure the impact of early season cold fronts or cold outbreaks for the south of the nation. At this time, there is no signal of it being early or later than normal.
Rainfall Outlook - Winter 2022
% chance of exceeding the rainfall for Winter 2022
The wet bias from the La Nina through Autumn will wane during the May next year and winter should resolve to near seasonal over eastern areas but coastal communities may still see prolonged colder southeast winds with showers for June before things dry out. At this time, seeing a drier bias for the west of the nation with a persistence of high pressure and a neutral IOD at this time. HOWEVER, there are some models that support the La Nina not quite resolving into winter and there are some models that support the reformation of the IOD into a negative phase. Lets just say this, not El Nino and positive IOD phase is low at this time. Will review this in early January.
Temperature Outlook Winter
% chance of exceeding the median temperatures for Winter 2022
Temperatures at this time, this far out, are leaning warmer than normal, there is not bias towards colder weather at this time, with a few members trending warmer through interior areas, so will placemark this for now. But being this far out, the forecasts will refine during January and February regarding this.
I will have an updated view on Autumn 2022 in the coming days and another update on this product on Tuesday next week. Many areas are leading towards some significant flooding and I must advise everyone reading this to prepare for not only wet and humid weather but the risk of flash and riverine flooding.