00:03Hello, it's Sunday the 23rd of August and this is your National Weather
00:06Forecast for the week ahead. Having a look at the current satellite image we
00:09can see that there's a bit of weather happening over the country this weekend.
00:12So we have a low pressure system sitting over WA and into the interior of the
00:16country bringing rain and thunderstorms with it. Down here in the south you can
00:21see this sort of cold air cumulus cloud which is behind a front that's bringing
00:25some cold wet and windy weather to Tasmania. Over the southeast though there
00:29is a high pressure system over there it's bringing some sunny settled weather
00:32across the weekend. Now let's have a look at the current weather warnings this is
00:36Sunday the 23rd we still have flood warnings up here in Northern Victoria
00:40minor and moderate flood warnings and we have marine wind warnings down in Tassie
00:44as that front moves through. Those marine wind warnings lasting until Monday
00:48and intensify down here in the south of the state and they also extend into
00:52South Australia as that cutoff low moves into South Australia. Let's go into the
00:57day-by-day breakdown of what's coming ahead this week. Cool so this is Sunday's
01:02daily rainfall accumulation or potential accumulation this is the cutoff low
01:06system that's going to be really driving a lot of the weather that we see this
01:10week. It's delivering you know 15 to 25 mils in its most intense parts and is
01:15associated with some thunderstorm activity across the region. As for Monday
01:19moves down here into South Australia bringing those wind warnings and rain
01:22across into some of the more populated areas in Adelaide a potential of 25 to 50
01:27mils there. For Tuesday it comes into the southeast falling again 50 to 75 mils up in
01:33the ranges again where we've seen a lot of flooding so there is a potential that
01:36that flood risk warning comes back again this week for a lot of Northern
01:40Victoria and it extends all the way up into Southern Queensland so quite a strong
01:45like wide extent rain system. And then you can see the next front coming through
01:49down here in Western Australia that arrives on land on Wednesday while this
01:55system mainly moves off into the Tasman delivering some onshore rainfall though
02:00up into the sort of north New South Wales southern Queensland coastal areas.
02:05Thursday this front starts to move through the east is now settled under a high
02:10and Friday it starts to move across again. Saturday it weekends and then Sunday we
02:16should be dominated by that high. Alright so that's the rainfall that we're seeing
02:21this week. This is the total accumulated fall potentials we're seeing. The yellow
02:24here being 25 to 50 mils and some of these darker patches being 50 to 75 mils.
02:29And what we're really seeing is that especially for the southeast these rainfall
02:33signatures are from a single day of rainfall whereas maybe in here this is a mix of
02:39the start of the week and then possibly a little bit from that front associated at
02:43the end of next week. After these sorts of rain systems move off though and the
02:47high settles in there's definitely a chance of frost and fog on the way for
02:51many regions. Okay that's it for this week's weather update we'll go into the
02:56seasonal forecast now. Okay into the seasonal outlook now obviously not a bunch
03:01has changed since last week because seasonal outlooks don't change usually too
03:04quickly so instead I thought today we'd actually have a little bit of a deeper dive
03:08looking at some charts to sort of understand what rainfall is on the way.
03:12This is the 75% chance sort of scenario of what is likely on the way from the
03:21Access S2 model which is the Australian or the Bureau's model. So it's sort of like
03:26the very likely or highly likely rainfall that we'll receive in September. Okay
03:32that's what we're looking at here. And to contextualize it I thought we'd compare it to
03:36last week's rainfall so all you have to do is think about how much rainfall sort of fell
03:40at your place last week and we can kind of compare the numbers today. So to start off
03:45let's look at this weekend the 22nd of August. So in this brighter green we're
03:51talking 25 to 50 mils which we saw up in this sort of central coastal region of WA
03:57and then as well through this interior bit of Victoria and New South Wales which is
04:03contributing to the flooding here in Northern Victoria. And then we have these pockets of
04:0950 to 100 mils up in Northwest Tasmania. Now that was just over you know Wednesday and Thursday
04:15last week and in little pockets of the interior here as well. So unless you're in this band or
04:22this little bit here the rest is sort of in the 1 to 10 mils. So that's what you experienced
04:27last week.
04:28Now let's map that to this chart where the 25 to 50 mils is this slightly lighter green.
04:36So what we're seeing is that the likely scenario in September is that across Victoria for the whole
04:45month of September you are going to experience about the same amount of rainfall as like eastern
04:53Victoria did in a single week. So I hope that's making sense. So across the month of September
05:00it's likely you will receive about the same amount of rainfall as you did last week.
05:05That's what we're seeing from the models. Okay. If you are here in southern WA you're going to get
05:16about 25 to 50 mils which is less than what you got last week. So a little bit more than
05:26last week
05:26across the whole month but only a little bit more. If I go into the one month okay we can
05:34see that the
05:35rainfall that you got across July which I know is a bit far away now. So all of the July
05:41rainfall which
05:42is 25 to 50 mils here in New South Wales for example you are only going to be getting for
05:49the
05:49month of September 1 to 10 mils. So I hope that's contextualizing what we're actually looking at
05:56here. And now that we have that in mind obviously we don't expect when we're looking at means you
06:02know July which is a winter month compared to September which is the start of spring. Obviously
06:06that should be a little bit different but that gives us a contextual understanding where we're coming
06:09from. Now if we look at the chance above the median rainfall of September we can kind of start to
06:16think or see what we mean by it being so low. So we have the models are showing us less
06:22rainfall on the
06:23way than you would typically see in the month of September. So I'm hoping that helps you understand
06:27or contextually put what the month of September's rainfall will look like and really starting to
06:33think about the impacts of El Nino. Speaking of El Nino we will have a very quick look. This is
06:40the sea
06:41surface temperature anomaly and you can see it is getting ridiculously hot in the Pacific and if we
06:47look at the end so the axes almost aren't capturing here what the models are predicting for it now.
06:55But that's really not a different story than what we've seen. You guys know that now we've got a very
06:58intense El Nino coming on the way. The southern annular mode is dipping here for strong fronts.
07:05This is largely sort of just picking up that cutoff low that's coming across this week in Australia
07:10which is basically just making the SAM calculation think that the storm track is sitting higher when
07:16it's just this sort of system moving through. But we are firmly in the sort of neutral phase of the
07:20southern annular mode which is why we're starting to get a few more of those rainy systems moving
07:26through which we were definitely missing at the start of winter. And then the Madden-Julian
07:31oscillation if you're up in the tropical regions is really sort of firmly within this central box
07:37which means we're not getting any strong phases of the MGO starting to impact any of the rainfall
07:42outlook up ahead. Okay so that's what we're seeing. I can show you the temperature outlooks but
07:50they're like there's just no point of looking at temperature outlooks really in the way that
07:56these are visualized. We have a high likelihood of exceeding the maximum median temperature in September
08:03from 1981 to 2018 because we always do now. Like this is just a climate change signal we're not really
08:10getting, like this doesn't really show us a good impact of what El Nino might do to the temperature
08:16in spring. So yeah that's just not a great visualization but in case you were wondering
08:21there it is. And even for the max temperature anomaly which maybe is a little bit clearer
08:28I suppose you can start to see the El Nino signal here a little bit in the east and here
08:33in the west
08:34and then this slight negative anomaly could be just with some more cloud associated coming through.
08:40Okay that's the long range forecast, that's our outlook for the week for the nation. Any questions
08:46let us know below but please be safe as that low moves through. It's got a lot of rain, wind
08:52and
08:52thunderstorm activity associated with it so yeah definitely be safe. Have a great week and we'll see you next time.
08:57So
08:58you
08:58you
Comments