00:02Hello Australia, it is Sunday the 25th of October and this is your weather update for the week ahead.
00:06There is severe weather across much of Australia with a lot of severe rainfall this week, okay?
00:11So looking here at the accumulations we can see that much of the eastern part of the country
00:13will receive 25 to 50 mils with pockets in Queensland and in some of the range areas
00:17receiving anywhere from 50 to 100 mils possible. So that is a lot of rain on the way that has
00:21been
00:21associated with sheet graziers warnings, severe weather warnings, thunder, lightning, possible
00:24hail and flood warnings, especially in the Queensland southern regions. I expect that
00:27to continue for a lot of this week, especially those flood warnings in Queensland as there is still
00:30a lot of moisture in the air. Before I get through into this weather, this daily sort of weather breakdown
00:34this week, I thought I'd discuss why is there so much moisture available at the moment. It's because
00:37of a few reasons really. We're going to start here looking at the Bureau's current weather map or their
00:40analysis chart and to look just at the surface level pressure of what's happening and then we'll
00:43discuss some of the upper level dynamics. So we have a cold front that's moved through the south and
00:45this is connected with a trough over the interior of the country. So those low pressures are what is
00:49a really key ingredient to driving rainfall but in order for there to be rainfall and such soaking rain
00:52that we're seeing there also has to be moisture available and there's a few reasons why we have
00:55moisture available. First is that we have this feed in from a warm Indian Ocean, so that's providing
00:59that tropical moisture there from the Indian Ocean. However, we also have this stationary high sitting
01:02in the Tasman delivering onshore flows, so also delivering this warm moist air that's travelled in
01:06from the Coral Sea and from the Pacific as well. So we have those two feeds of tropical moisture coming
01:10in and then we have this low pressure over the interior of the country that's allowing those to
01:13eventuate. The other reason that it's so strong is because there's quite warm air from these
01:16northerly flows and warm air is a really key ingredient to getting convective systems, convective
01:19systems being what is what drives some thunder and lightning storms. So those are I suppose a lot of the
01:24ingredients occurring behind the severe weather that we're seeing at the moment. Okay, let's have a look
01:27at the day-by-day breakdown of what's occurring. So this is Sunday, it does seem to be the worst
01:30day
01:30for the southeast regions as that front moves through. Into Monday, most of the southeast has
01:33dried compared to that Sunday rainfall but northern New South Wales and southern Queensland still a lot
01:37of rain on the way and then we have another sort of low pressure system in WA driving this moisture
01:40band here in the Northern Territory. All right, trough action over the interior of the country for
01:44Tuesday, Wednesday, Thursday. You can see this cutoff low now sitting over South Australia and again
01:48continuing up into a lot of this severe weather in the territory. Cool, Friday we start to see it coming
01:53back over again
01:53into Queensland so that's why I say those flood warnings will likely continue to be issued throughout
01:56the week even if there's a day or two that you get a bit of break from the rain. Here's
01:58Saturday as well,
01:59rain on the way here. You can see the high pressure system in the bite moving over that should hopefully
02:02dry out the east coast into the start of next week and you can start to see a little bit
02:05of that
02:05dryness on the way there for Sunday but still just heaps of moisture available. If you take anything
02:08it's a wet week ahead. I've not seen super significant winds on the way but there are still definitely
02:13moderate to strong winds on the way with a lot of that rain so definitely something to be
02:16considerate of. As for the hot temperatures that we saw last week, we're not going to see as much heat
02:20across most of
02:20Australia this week. The rainfall has definitely cooled it down but it's quite humid so even though
02:23for a lot of say for example the southeast we're now in the 20s it's that humid heat so definitely
02:27still something to be conscious of when you're working outdoors. All right that is it for the
02:30weather update. I thought we'd touch in this week in our long-term forecast with the Indian Ocean
02:33dipole because this is the first time I've seen a consistent trend called for many many months now.
02:38So for months we've seen the Australian and the Japanese models and a lot of other models as well
02:41diverge whether it's going to be a positive or a negative IOD. This is the first time I'm seeing these
02:43two models
02:44both trend negative so Japan into a negative IOD wetter and the Australian at least going into a neutral.
02:48This is good news and possibly one of the reasons why it's been such a wet El Nino year. Definitely
02:52something we can chat about more if you're curious why it's been such a wet year even though we have
02:54an El Nino being called. All right the other thing that I want to highlight is with our seasonal
02:59forecasting so we're looking here at this week essentially the 29th of October to the 4th of
03:02October. This model was run on the 22nd so three days ago from when I'm videoing this weather update
03:06from the Bureau's Access S2 model and why I'm bringing it up is that I want to talk to my
03:11colleagues
03:12further to discuss why this model is showing that it's unlikely to exceed medium rainfall across much of
03:15Queensland when we know through the numerical weather processing or the numerical weather
03:18forecast which is our short-term models that there's a lot of rain on the way this week.
03:21So why I wanted to bring that up even though I don't have answers is to show you what scientific
03:24discourse is like. I suppose to be honest I'm not an expert of seasonal forecasts and how they
03:28operate or run. Neither are most of the people that write articles about it that you're reading
03:31online however you know often independent singular people will make an analysis from this and just to
03:35show you that as a scientist that I would not go and make you know judgment calls about things
03:39without consulting with my colleagues first. So the point of this is that something funky is happening with the
03:42models. I will come and investigate that this week with my colleagues and next week hopefully let you
03:46know why it's showing to be so dry even when we know it's quite a wet week ahead. So I'll
03:49leave you
03:50on that little piece of I suppose future analysis to occur. Okay finally let's wrap up here just
03:55looking at the rainfall totals again to show you lots of rain on the way this week so severe weather
03:58definitely possible. Please be safe. Have a good week and we'll see you next time. Bye!
