The polar vortex is a large area of low pressure and cold air that sits over the Arctic. During winter, the polar vortex can sometimes become elongated and stretch down into the mid-latitudes, bringing cold weather with it. This is what is happening at the moment in Australia.
The cut-off low-pressure system is a small, isolated area of low pressure that has become separated from the main jet stream. This system is currently sitting over southeastern Australia and is helping to keep the cold air in place.
The cold weather is expected to last for several more days, but it is gradually starting to warm up. The polar vortex is expected to weaken in the coming weeks, and the cut-off low-pressure system is expected to move away. This will allow the cold air to start to retreat.
In the meantime, Australians are advised to stay warm and to take precautions against the cold weather.
