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Stay informed with the latest weather forecast video, covering rain patterns, temperature outlooks, and severe weather warnings. Updated every few days with expert analysis, from Weather Scientist Alex Dunne.
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00:03Hello it is Sunday the 9th of August and this is your national weather update. We're going to go
00:06through a very quick glance around the country for the weather of the week but we're going to
00:10spend a little bit more time looking at the seasonal outlooks as well as some of our climate
00:14modes and how they're developing as well. So let's get into it. First off here we're looking at the
00:19Sunday midday satellite image and you can see this very strong cloud band along the southeast as a
00:24strong front moves through bringing lots of wet windy cold weather. You might hear this referred
00:29to as a warm conveyor belt or an atmospheric river and really what it is is just this very well
00:34structured formation in the atmosphere that can deliver a lot of moisture on the ground. So
00:39that's what we're looking at there. This is resulting in several strong weather warnings
00:44across the nation. So pretty much across the entire southern part of the country we have coastal wind
00:48warnings. In these interior parts of South Australia and Victoria and New South Wales we have strong wind
00:54and strong rainfall warnings and we also have down in Victoria flood warnings in those already very
00:59moist soil regions. This is our rainfall accumulation for the week so we can see a lot of concentration
01:05again in the ranges but wide parts of the southeast are going to be getting 25 to 50 mils of
01:11rain which
01:11is a lot of rain. We're also getting some of that extending up into the central parts of the country
01:16with showers so anywhere between so one and five mils for most of the southern part of the country
01:21with regions experiencing sort of 5 to 15 as well. This is the system in question that we're talking
01:26about. This is what it looks like on Sunday. We've got this low pressure system moving across over
01:30Adelaide and into Melbourne and then just to show you Monday it moves across and delivers a lot more
01:35of the rainfall into the ranges then and then we have a second front that's moving through in WA and
01:39coming across to the east and it should get the east sort of Tuesday night, Wednesday morning. So those are
01:44the
01:44two active systems, the fronts that are moving through. After sort of the start of the week we
01:49have high pressure settling in delivering some cooler overnight temperatures for much of the
01:54country but not super super chilly. I wouldn't say it's a widespread frost risk. There's definitely areas
02:00that will be experiencing frost but it's not massive massive areas. Okay so that's sort of the weather
02:05that's happening this week. Let's start looking into the long-range forecasts and starting to unpack them.
02:09First off I want to show you like the current state of where we are in terms of rainfall and
02:14soil moisture
02:14that we've received. Okay so here we are looking at the Bureau of Meteorology's AGCD products. Now these
02:22products you know have some bias correcting or interpolation tools which means that the rainfall
02:27that you see here isn't exactly what you would have experienced on ground but that's sort of you know
02:31roughly the patterns that we're seeing in terms of the systems that are moving through. So we're looking
02:35at July's rainfall here so the past month. This is the rainfall totals but we're going to move on to
02:40deciles now just to show the difference. So just because we've had rain doesn't mean that it's the
02:44same amount of rain that we usually get in July. So WA has been very dry as well as a
02:51lot of the east
02:52coast. Now the east coast is what we definitely expect when we have an El Nino which we're currently in
02:59and then this dry Western Australia is also quite typical of the positive IOD that we're starting to
03:05sort of trend towards as well. And then we have you know just actually quite a bit of moisture in
03:10the
03:10interior. Now this is also you know if we go back to the actual rainfall totals that's largely driven
03:16by sort of one maybe two systems and it's just because not a lot of rain is typically experienced in
03:22those central areas. So if we get a system that happens to deliver you know sort of five to ten
03:26mils that
03:26can actually accumulate to a lot in terms of the monthly average. So that's all we're sort of seeing there.
03:32If we go to three months so now we're talking May to July so really a lot of this sort
03:36of autumn
03:37to sort of current winter rainfall which is when we start to experience a lot of rainfall. Most of
03:42Australia in the southern half gets sort of winter to spring rainfall. It's actually sort of average
03:47to very much above average especially across these interior parts again but it's these coastal
03:53regions in the east that I think a lot of that ENSO pattern is starting to throw out there.
03:59Let's have a look at the drought indicator. So this is three months drought and it's just picking up here
04:04on southwest WA. Cool. So that's just a bit of an update of where we actually are at the moment
04:10and
04:10let's start discussing what it looks like we're going to go ahead into. So here we're looking at the two
04:15week forecast. So the 13th to 26th of August just so that you can sort of help plan your next
04:22few weeks.
04:22This is the 75% chance scenario. So this is saying this is highly likely according to how the models
04:28are currently running that we're going to be experiencing rainfall and the two week band sort
04:33of weather prediction is relatively good. So this is you know pretty decent chance. So we're going to
04:39be getting sort of one to maybe 25 mils in WA. This is very much the pattern that we've seen
04:46over the
04:46last few months of how the fronts are moving through. Same here across sort of southeast Australia and then
04:52Tassie the western range is always getting a little bit more. And if we go to the 25% chance
04:56scenario so it's less likely. What I want to mainly point out here is that that is a very similar
05:02pattern. It's this sort of extension of the the orange colors which is like light rainfall is more
05:10about if the fronts are moving slightly more northwards or not. So yeah I think there's pretty like
05:17pretty good coherence in the models that it's just these sort of weak fronts moving through. These
05:22these are fairly weak fronts in the next not after this week but the next two weeks and that's a
05:26fairly decent sort of outlook of where we're going. I want to now do um let's do the first
05:31three months so heading into spring now which is when we um typically expect a lot of our rainfall
05:37to come to the southern parts of Australia. This is the 75% chance of exceeding September to November.
05:44Okay so like the quite likely chance um of rainfall. So we've only got sort of 50 to 100 mils
05:52here in
05:52the model along the coastal regions and in the interior sort of 25 to 50 mils. So this is not
05:57a lot of
05:58rainfall on the way and even this west coast of Tasmania um that's just a lot of orographic
06:03lifting there that's that's not from particularly strong systems hitting Tassie either. So yeah that's
06:07not a lot of rainfall on the way for the 75% chance scenario. 25% chance scenario here we're
06:13looking at
06:13100 to 200 mils across most of the sort of um ag districts with maybe like the sort of 200
06:21to 400 mils
06:22in the ranges. So again I'm not seeing a massive difference here um it's more the strength of the
06:28systems but but yeah what we're looking at is really not a super wet spring fall um which is expected
06:38during ENSO and we'll keep checking in on this um we'll definitely keep coming back to it but yeah
06:43that's not a ton of rain on the way. Okay so let's have a look now at our climate drivers
06:48just to see how
06:49they're developing. This is the sea surface temperature anomaly and you can see this um this
06:54is one of our ENSO boxes it's quite warm it's very warm actually and if we go into our ENSO
07:00we can see
07:01that um a lot of the models are showing a stronger El Nino on the way. This is the ECMWF
07:07so this is we're
07:07just showing one model which is the European forecast model but I'm showing you their ensemble members so
07:11they run lots of different models and we're seeing how those models agree. They are starting to
07:16I would say come to a much stronger agreeance on the strength of this El Nino so it's looking like
07:21it will be at least a three degree celsius anomaly which is a very strong El Nino and it's looking
07:26to
07:26peak sort of maybe November, December I would say is where the models are sort of showing it to peak
07:33as
07:33well. Okay just to show this um image one more time I showed this a few weeks ago in our
07:39ENSO update
07:39is just to show that the observations which are here in this black line are very much trending towards
07:46the stronger half of the models. Now this is I think kind of no longer surprising when we first
07:53started talking about El Nino being declared sort of back in May or April we had much greater spread
07:58in the models of where it was going to go how it was going to develop and it was going
08:01to peak.
08:02This is as always so um El Ninos develop and intensify during winter so by the towards like
08:09the end of winter start of spring we start to understand what they're going to look like a
08:12lot better. The models are just more capable of seeing how they're going to develop and that's
08:16why we have so much more strength than where this is going. Um so yeah I'm not surprised that this
08:21is
08:21remaining trending towards the high side of the models just based on how this ENSO is developing
08:25which yeah is to also show that it's it's very strong El Nino that we're going to talk about.
08:30Okay so that's the ENSO update um it's intensifying we're starting to see that impact the seasonal
08:38forecast this long-range forecast of rainfall um but yeah we'll we'll keep monitoring it and how it
08:45develops. Okay let's check into some other um climate drivers because El Nino and ENSO are not the only
08:51things that drive our climate. Weather is what delivers rainfall not El Nino um El Nino sort of
08:57helps shape what the weather systems that will be that arrive um so it's important that we're checking
09:01with others as well. So this is the Southern Oscillation Index and it's often a pretty good
09:05indicator of ENSO activity and a negative Southern Oscillation Index is usually indicative of an El Nino
09:12which is where we're heading and that looks you know quite on track. The Indian Ocean Dipole this has
09:18across the year had such divergence in the models of where it's going it's currently trending towards
09:23a positive IOD. Positive IODs also bring drier hotter conditions to Australia so we could potentially be
09:29going into a El Nino and positive IOD um spring summer. Southern Annular Mode. Southern Annular Mode is
09:39the contraction or extent sorry the contraction or the extension of the sort of westerly wind belts um it was
09:46very positive like record-breaking positive uh a few months ago when like in July sort of end of
09:53June start of July very very positive which is one of actually the reasons that we didn't get a lot
09:58of
09:58the winter rainfall that we're expecting down in the south not ENSO um because the fronts they were
10:04developing and they were delivering but they couldn't extend up across into the actual interior parts of
10:09the country so they were very southern um which is why if we look at the rainfall history if I
10:14go into
10:14rainfall deciles for the month um Tasmania it's relatively like average rainfall they were still
10:19getting their rainfall and even into parts of Victoria but the fronts across here weren't um developing
10:25up and penetrating across so that's just part of the Southern Annular Mode point is it's heading back
10:30into neutral and that's why we've gotten to discuss over the last few weeks that we're starting to get
10:35more of that frontal activity coming across and into the southern parts um it is however it's it's not
10:41going into the negative so we're not going to see strong fronts it just is the return of those more
10:47typical winter fronts that I feel like we've been missing a lot throughout the start of winter okay
10:51finally wrapping it up with the Madden-Julian oscillation so if we go back into here which is
10:58rainfall 75 chance scenario and let's do the second fortnight um
11:06actually let's go chance about the median this shows it well so um very low chance of exceeding
11:12median rainfall down here in the south but there's actually a chance of exceeding it up here in the
11:16north now it's a dry season so sort of any rain is going to exceed the median and that is
11:20largely because
11:21the MJO the Madden-Julian oscillation is starting to enter some of its wetter phases so um likely delivering
11:27just probably you know not heavy rainfalls but light to moderate rainfalls could be on the way in the
11:31next few weeks up in the north as well okay so that's that's a very long discussion on sort of
11:38where we're at and where we're going um I think it's pretty safe to say that we will be discussing
11:43El Nino and so a lot more um you're going to be seeing it in the news everywhere and I
11:49know it's
11:49a very important indicator for a lot of people about what you're going to plant in this spring
11:56season whether to destock all those sorts of decisions so um we will I think be paying a
12:01little bit more closer attention to this so in the next few videos I think definitely in our
12:04national updates we'll be going through this every week um don't be surprised if they're the things
12:10that we discuss each week don't change um but I'll still go through it just to you know keep you
12:14in
12:14the loop of how it's developing and what we're seeing but for the most part um yeah we're definitely
12:18seeing much more confidence of its intensification but as a reiteration a strong El Nino does not mean
12:25strong drought conditions okay if you don't quite understand where that comes from there's a video
12:30posted maybe a little bit over a month ago where we just go and explain El Nino so you can
12:34go back
12:35to there um and check that out or if you have some more questions or want anything clarified please
12:39reach out to the Jane's weather team or the farm online weather team and they'll pass it on to me
12:43and we can discuss that next week okay do have a good week stay safe and let us know if
12:47we can give
12:48you any more information that will be helpful see ya
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