We all know what a cold front is. But what about warm fronts? Why do we hear so little about them, and what exactly are they?

Here at Weatherzone, we've written twice this week already about the strong cold front coming to southeast Australia this Friday, not to mention plenty of recent stories about cold fronts lashing southern parts of SA, WA, Tasmania, Vic, and NSW.

Cold fronts, cold fronts, cold fronts. Even in the very mild winter of 2023, we've talked a lot about them, and everyone understands the sort of weather cold fronts deliver, even if they don't live in the southern half of Australia.

But warm fronts are a thing too, and you can see one lurking ominously in the Southern Ocean west of Tasmania in our chart for Friday evening.

In simple terms, a warm front is the boundary between a warm air mass and a comparatively cooler airmass, where the warm air is advancing into the cooler airmass.

The red line indicates the location of the boundary between airmasses.

But how does warm air get down there in the Southern Ocean?

It's transported there. Just as Southern Ocean cold fronts push polar air northwards over Australia, comparatively warm air can be forced southwards.

In the case of the chart above, air from the mid-Indian Ocean has reached the Southern Ocean after circulating all the way around the large high pressure system centred west of Perth.

Are the effects of warm fronts as dramatic as cold fronts?

They're different. Warm fronts don't tend to arrive with a dramatic temperature change over a short period of time, although they can bring significant precipitation which tends to fall in a steady and prolonged manner, especially in areas like western Tasmania.

Warm fronts might not always be quite as dynamic or exciting as cold fronts, which is why we don't talk about them much. But they're definitely a thing.