Australia: This Massive Storm Will Hit Brisbane...

Added: 2026-05-19

[00:00:01]Good day folks. It's Josh here from Cyclones Oz and this is your afternoon broadcast on the rainfall storms that are developing across Queensland and New South Wales for the 18th of May 2026.

[00:00:10]Ments falls are beginning to develop in this region and I thought that it'd be worthwhile taking a look at these this afternoon. But first, if you are brand new to my channel, please do consider subscribing. Let's get stuck straight into the details right now. As you can see on the radar imagery later this morning, we are beginning to see some significant amounts of rainfall pouring in off the coast. And that's all thanks to this coastal flow here coming out of the northeast wrapping around a high pressure system situated over New Zealand right now. This entrainment of rainfall is getting squashed between an event moving in here from the west. and this squash zone that's developed along the coastline which is actually expected to get stronger this afternoon into this evening and into the later hours of tonight when rainfall is expected to be at its heaviest coupled with deepseated atmospheric moisture and very warm sea temperatures offshore from this portion of coastline is giving us some of the heaviest rainfall we've seen in months over Queensland and New South Wales in fact in some areas this is the heaviest rainfall outside of a severe thunderstorm since tropical cyclone Alfred moved through the region back in early 2025 so quite significant at this point in time and you can see just about to jump the border over into northeastern New South Wales. If we quickly pause on the latest radar imagery and have a look at what these rain rates are doing, you can see in a few of these showers and thunderstorms here beginning to get up to about 50 or 60 mm an hour in places. Uh a few spots here getting closer to 70 mm an hour.

[00:01:26]So, we really are looking at some pretty intense rainfall. And you can see it is very very widespread, very consistent here as it pushes into the city grim and the southern side of Brisbane. It does look to be to me at least that Brisbane's southern side is going to see the bulk of the rainfall right now. And you can see just as the afternoon gets uh or further into gear, you can see this rainfall is only getting heavier as it gets squashed up against the border ranges down here and more moisture becomes readily available into the atmosphere as it pulls in from the west here. So, we're really starting to get a culmination of converging events here favoring rainfall across southeastern Queensland and northeastern New South Wales. Let's look at it now on the convective allowing forecast models hour by hour starting at about 300 p.m. this afternoon when this video is expected to be out. You can see very heavy rainfall beginning to cross the border into northeastern New South Wales in a few spots likely to be around that 20 to 50 mm an hour mark. That's enough to get some flash flooding off the ground. And we have to keep in mind that we've already got some significant rainfall already over these regions. So rivers are going to be a lot quicker to respond this afternoon when rainfall does come through. The entrainment of showers coming in from the northeast this afternoon will continue to bolster rainfall accumulations particularly through the border ranges. And you can see that's going to be a consistent picture through this afternoon and into this evening with those border ranges being the focus of this rainfall.

[00:02:40]Continues to get heavier as we get out to about 7 or 8:00 right now. More rainfall expected to pull into Brisbane.

[00:02:45]The Sanford Valley and some of the western suburbs should be really in the thick of things right now with rainfall and a lot of rainfall beginning to pull down the New South Wales coastline as well. About as far south as Port McCory.

[00:02:55]You can actually see it here on the Sydney sector of the cam. Some good rainfall accumulations beginning to push into those regions. Now, we need to zoom out here to understand why that's the case. Of course, that northeasterly flow is expected to peak later this afternoon and into this evening between about 5 and 8:00 p.m. And then that low pressure system, the surface low developing out here in southern Queensland is expected to push into the vicinity of this onshore flow. So, that's where that squash zone really does come into effect. And you can see those winds, northwesterly through here, northeasterly through here. They're going to create an area of relatively weak convergence all things considered, but it is going to be converging enough to generate rainfall. And particularly with how strong the flow is coming ashore once that gets itself jammed up to the hills and mountains adjacent to the coastline, it's going to be all evaporation town from that point onwards. And that's where the significant rainfall is expected to really ramp up. It does look right now that the focus of the heaviest rainfall is going to be between about 10:00 tonight and 2:00 early tomorrow morning.

[00:03:49]And the focus of the absolute heaviest rainfall is going to be around the border ranges and through far northeastern New South Wales. But that's not to say that southeastern Queensland is going to miss out. There will still be some relatively respectable falls around the scenic rim into the uh I believe it's the not the Glass House Mountains, the Gold Coast hint and far.

[00:04:05]It's been a while since we've talked about this area in such great detail and of course the Gold Coast itself. Now, rainfall accumulations are quite interesting and I said this morning in a Facebook post that the convective allowing models here from the Access C Brisbane sector are likely to be overbing some of the rainfall accumulations. I no longer believe that to be the case considering the setup and we'll talk about that in great detail in just a few minutes. You can see rainfall accumulations over laid here. Bruisie looking at about 100 millm event wide.

[00:04:31]So, keep in mind that this is eventwide rainfall accumulation. So, this includes what's already fallen plus what is expected to fall. A lot of these areas, particularly into the southern and western suburbs of Brisbane, as well as around the Morton Bay area, have already picked up between 50 to 75 mm of rainfall, likely by the time this video is out. So, you're probably about 40 to 50% of the way through this rainfall event here. Likely to see a further 100 millm down onto the Gold Coast could increase to as much as 150 mm closer to the border ranges. And if we really zoom in here, places like Springbrook and around the Nang Dam area, not the Nang Dam, but where the Nang River originates here into the upper Springbrook area could see a further 150 mm giving us eventwide accumulations of 150 to 300 mm there. And I believe that to be a possibility just given how intense the rainfall is right now and the fact that this afternoon is expected to be the wetest kind of period here. Heavy falls expected over at the border into northeastern New South Wales. Now, the bulk of the rainfall is still yet to come for northeastern New South Wales.

[00:05:27]So, when we're looking at these numbers here getting closer to 200 millimeters, the majority of that is actually going to fall tonight, which is really going to raise our flash flooding concerns through here. We've got significant rainfall potential around Tweed Heads, the Gold Coast, M Willar, and right down to Lismore, Grafton, and Yamber. There's going to be at least 100 millimeters in these areas, particularly for those traditionally wetter locations in more elevated areas adjacent to the coastline. Good falls also expected further inland as well out to Tenderfield, Inverel, Armadal, Narright and Mor. Uh out here we do have kind of a bit of a split zone. Showers will make their way out towards Tenderfield down to about Armadal later that tonight into early tomorrow morning and that could give us 30 mm in the gauge out there.

[00:06:05]But then it's going to be the westerly moving influence from that low pressure system coming in from the west along the Queensland New South Wales border where more steady rainfall accumulations are expected between 15 to 30 mm out here on top of the rainfall that comes through from showers. So a couple of spots particularly onto the kind of western periphery of the foothills out here from the great dividing range. So running from about Warrick down to about Armadal there could be falls approaching 50 mm through here which is excellent considering how dry these areas are. But as you get further inland out to Mory Narbry and then even further inland towards get lightning ridge and uh I guess out towards the outback communities rainfall accumulations are actually going to be a little bit lighter out there uh compared to what the original forecast has been. And again, that's just because of that low pressure system. Whilst it does have some bite to it, it really isn't all that significant. And you can see that quite clearly here on the radar imagery.

[00:06:54]We do have some good rainfall out here, but it is pretty light in nature, all things considered. And it is also quite patchy. Of course, the focus of the heaviest rainfall here adjacent uh to the coastline uh which is quite concerning. Now, we do currently have a flood watch in effect, and I want to just quickly pull up the drought monitoring map and show you where that flood watch is currently in effect right now. Keep in mind the drought monitoring map is a couple of days out of date at this point in time. So deep uh deep moisture through here into the soils across southeastern Queensland, but especially into northeastern New South Wales, very much above average. And that's because we've had a relentless onslaught of showers in the past couple of weeks, pretty much since Anzac Day.

[00:07:30]It's been non-stop for northeastern New South Wales. And as a result, coastal areas are actually much wetter than average. Also includes portions of southeastern Queensland around the Gold Coast near the Mud Islands, Strabro Island, and up towards Morton Island.

[00:07:43]very significant soil moisture values up there and as a result rivers and creeks going to respond very quickly to any rainfall that occurs in these regions.

[00:07:49]We're already seeing some localized flooding as a result. We're not expecting anything too crazy or significant. Major flooding is not really a possibility or a concern from this weather event here. Minor flooding will likely extend through portions of northeastern New South Wales as we head in towards early tomorrow morning.

[00:08:03]Moderate flooding is a possibility and it could extend into the Albert River, for example, but it's a pretty loose possibility right now. Keep in mind a lot of these areas are still quite dry all things considered. Further inland, we're not going to see enough rainfall and coupling that with how slow rivers will be to respond just considering how dry it's been out here. Flooding isn't really a concern through this portion of New South Wales and also southern Queensland. But some good rainfall out there could top up dams and give a bit of a green tinge to paddics which would be very very welcome indeed. But yeah, definitely one of the more significant rainfall events we've seen in recent uh weeks and months in this region. and it is expected to get heavier as we head out towards tonight. Let's just briefly talk about why this rainfall has actually been very significant. And uh this is over on the Cyclones Oz website.

[00:08:46]Uh we've really we're overhauling the game here. Obviously, this isn't publicly available yet, but we do have a sea surface temperature map uh over on the Cyclones Oz website, which will be launching on the 31st of May. So, that's going to be Sunday, the following Sunday. Mark your calendars. You don't want to miss it. Plus, our email subscription service starting at just 10 bucks a year. an absolute armed robbery that is uh for weather information. But the sea surface temperature map is what we're here for right now. You really have to zoom in here and if I remember to crop in, you're lucky. If not, you're unlucky. But you really have to zoom in here to see the eastern coast of Australia at this point in time. But it is running in those warmer than average colors, specifically between 1° and 3° C above average. Gets a little bit warmer the further down the New South Wales coastline you get, but you get the picture. Much above average sea temperature values. Now, I use this analogy all the time, but a difference of 1 to 3° in ambient temperature isn't really that noticeable. But a difference in sea temperatures or overall average temperatures when compared to the long-term average, that's a big big deal. And in this case here, it is significantly warmer than average. 1 to 3° is no small feat here. And that is why we've seen such a significant onslaught of showers in recent weeks and months because of how much warm water and how much energy is available for those showers to captivate here as they move into our coastal portions of New South Wales and Queensland. And in this event here, it is no different. If we move over or move back to the sea temperature map here, when we've got waters here pushing 24 25° offshore from southeastern Queensland, anything that comes in from the coastline is just going to have an absolute field day.

[00:10:17]It's going to evaporate very readily.

[00:10:19]It's also going to be very moist in uh nature. And given that this shower event is actually a little bit different, I mean, if we actually have a look at our windstream lines here, a lot of these showers coming in from the northeast, which means they're getting tropical moisture instead of subtropical moisture associated with them. That's really enhancing the amount of rainfall that we're beginning to see here through southeastern Queensland and northeastern New South Wales. And that in essence with the squash zone driven by that low pressure system advancing in from the west is why we're actually expecting to see so much rainfall through northeastern New South Wales and southeastern Queensland. It's not a case of the forecast rainfall being wrong once again. It's just a case of uh numerical forecast models cannot pick up on this sort of data. And of course when we look at the 3 to 7-day forecast we have to go off the numerical forecast.

[00:11:01]But I always had this hunch and that's why I've been saying 100 mm is a possibility over the last couple of days through northeastern New South Wales and isolated portions of southeastern Queensland. It will remain around the coast, but it was always going to be a possibility. That was my reason behind it was how warm these sea temperatures are currently adjacent to New South W.

[00:11:19]So pretty significant and especially for this time of the year. Very significant indeed. Just zooming out to encapsulate the entire kind of rainfall event that we're beginning to see here. Let's just get an idea of how large this system is.

[00:11:31]So extending from the northwest through here, you can see it runs over intowards Queensland and then it continues to move down well into the Tasmin Sea. You can see this one here, 3,300 km and it goes for another 2,000 km beyond that Queensland point that I've just put there. So nearly 5,500 km this uh clan band extends for. It is absolutely huge.

[00:11:52]One of the biggest that we've seen uh over the last couple of uh months here around Australia. It's one of the biggest examples of the northwestern cladband and it really is influential.

[00:12:00]It's a massive storm system and it is causing what's about to cause all sorts of flood related problems through northeastern New South Wales and southeastern Queensland. Pretty interesting to see, especially like I said given the time of year. And you can see just in the time that it's taken me to record this video, the rainfall is continuing to increase here through the southern suburbs of Brisbane. The focus of that heavier rainfall and an intrainment of showers coming in for through the Sunshine Coast and around the Fraser Coast as well. And we're going to continue to see that pick up and enhance throughout the course of today. So, this really is, you know, a bumper period of rainfall that we're beginning to see unfold across southeast Queensland and northeastern New South Wales. Very significant, like I said, for this time of the year. Twice daily updates. Can you believe it in May? I don't think we've ever done that before, unless it's been a really significant event, but we're not used to doing that here. Uh, if you are enjoying the twice daily updates, then please do consider leaving a like and also subscribe to the channel if you haven't already. Stay safe, stay off the roads over the next 24 hours here, and enjoy the rainfall because it is, especially for inland locations, much needed. and has been in anticipation for the last couple of weeks. So very very excited to have it finally showing up here on the forecast modeling. But that's going to do it for me today. I do hope you've enjoyed this second iteration of the updates and I'll catch you on the next storm. Goodbye.