Cyclone Narelle Update: Severe Weather Alert

It's just gone 9 am out west and let's check out the latest satellite imagery to see where Narelle has been overnight and what it's been doing. And the main thing it has been doing is strengthening, intensifying as it has moved away from the Kimberley coast and into the Indian Ocean. It has become a category one tropical cyclone once again, and this is only forecast to increase.

Currently, Narelle is just over 200 km to the north-west of Broome, and it's moving at around about 20 km an hour in a south-westward trajectory that's going to take it parallel to the Pilbara coastline over the course of the rest of the day. Today, we can see the latest in the forecast track here. It is likely to move in that south-westward trajectory while continuing to intensify.

So Narelle could be a category two tropical cyclone by the end of the day on Wednesday, then continue to build into a severe category three tropical cyclone during Thursday morning. But that is not the end of it either. We continue to play out the map and we see a category four on our map. Narelle likely to really strengthen through the next few days, could reach this category four strength. That is a really powerful, really major weather system. By around the end of the day Thursday, and then into Friday we will see this start to shift to the south, and we'll talk more about that a little bit later on.

But for now, let's focus in on the Tropical Cyclone Watches and Warnings which are in play for the moment for the next couple of days. And they are these orange and yellow areas on our map here. So we're mostly looking at areas along the Pilbara coast which are likely to be impacted by Narelle in the next 48 hours or so.

The Tropical Cyclone Warning, we've actually got two regions. A small area here up around Beagle Bay that's really just for the next few hours. The winds will ease there on Wednesday, and then the focus for the remainder of Wednesday into Thursday into Friday will be the Pilbara coast, where we've got warnings in place from Bidyadanga, which is just south of Broome, all the way through Port Hedland, Karratha, Onslow out towards Exmouth. At the moment, the watch area, well, we expect that to turn into a warning in the next day or two, but that goes through Coral Bay and down as far as Carnarvon.

So across this region, the main risk in the coming few days will be damaging to destructive winds, particularly along this stretch of coast from Karratha to Coral Bay. We could see wind gusts in excess of 140 km an hour there later this week. There will also be some really large waves along this coastline and some abnormally high tides so take care near the water and bands of rain and storms expected to sweep through, even though a lot of the rainfall will be out over the Indian Ocean.

Now let's go a little further ahead into the future, see what happens after Narelle starts to move southwards. It will continue to move at a fair rate of knots as it travels south, and it will gradually drop down through those numbers. That's going to mean it goes from a category four to a category three tropical cyclone on Friday, before reaching the Western Australia coastline. Then it is likely to make its coastal crossing probably in the very early hours of Saturday morning.

Based on current forecasts that coastal crossing is most likely to occur along the Gascoyne coast between Carnarvon and Kalbarri, likely somewhere around the Shark Bay and Denham area as a severe category three tropical cyclone. Beyond this, Narelle will continue to move southwards, now gradually tracking inland. That path would take it to the east of Perth over the Wheatbelt, the Great Southern and down towards the Esperance coastline. This could occur as a category one tropical cyclone, but maybe it will have already fallen back into a tropical low pressure area by the time it gets near Perth.

This will bring some widespread weather impacts to the west coast of the state as we head through Friday night and into the weekend. This is how that could look. While Tropical Cyclone Narelle will be up in the far north-west, we will see some rain and storms building over the Central West and moving into Perth for Friday, so we could already get quite a bit of rainfall ahead of the arrival of this system. But the main band of rain and strong wind will be when this moves southwards across all western districts of Western Australia.

Compared to what we were looking at yesterday, perhaps this could all occur a little bit faster, which means by the very end of the day Saturday, the cyclone is already somewhere near the far south coast, potentially ready to move off into the southern ocean early on the day on Sunday.

Finally, the last thing we'll look at in this video is a little look at rainfall accumulations that could occur both ahead of and with the tropical cyclone as it moves southwards. Widespread heavy rainfall expected all the way from Port Hedland and Exmouth all the way down to Bunbury and Albany. Some of our heaviest falls likely to be between Geraldton and Bunbury, including around the Perth area, 50 mm to 100 mm for many in that region. Certainly some places could see more than that. That is absolutely enough rainfall to lead to flash flooding or rivers rising and bursting their banks. So flooding does remain a distinct possibility and a distinct outcome as this weather system moves south.

We've got several more days of Narelle to watch, follow, track and warn for, so stay up to date with the latest warnings and SES information throughout the rest of this week and this weekend. Thanks so much for watching.