It's not going to be nice out there, let's be clear about that. But Sydney, Brisbane and the east coast will hopefully be spared the worst of the weather that slammed the area just two weeks ago.
SO WHAT'S GOING TO HAPPEN?
There will be rain. Organise a barbie at your peril. But as things stand on Friday, there are no specific warnings. The only official Bureau of Meteorology warning for the eastern half of Australia is a general flood watch for southern and central Queensland.
HOW MUCH RAIN?
Rain totals from 50 to 100 mm are expected over a wide area, which is excellent news for farmers. The rain should be significant but slightly less heavy as you move south through NSW, with only minor totals around 10mm expected on the Victorian border.
COULD IT BE WORSE THAN ALL THAT?
Yes, of course it could. There will likely be localised flooding in some areas.
YEAH, BUT WILL IT BE?
Buy a crystal ball, even the Bureau won't answer that.
I HATE RAINY WEEKENDS
WHAT'S GOING ON? IS THIS NORMAL?
So glad we asked ourselves that. You bet it's normal. What we're about to have here looks like being an east coast low. Here's what the Bureau says about them.
East Coast Lows (ECL) are intense low-pressure systems which occur on average several times each year off the eastern coast of Australia, in particular southern Queensland, NSW and eastern Victoria. Although they can occur at any time of the year, they are more common during Autumn and Winter with a maximum frequency in June.
SO ECL SYSTEMS ARE MOST COMMON IN JUNE
Yep. Bureau said so.
SHOULD WE DRAG CLIMATE CHANGE INTO THIS DISCUSSION?
Probably not in this instance. June is already tracking to be way warmer than normal. We're talking two degrees Australia-wide. East coast ocean water is warmer than usual too, which could be a factor. But there's no well-established link between the formation of ECLs and a warming climate.
NOW FOR THE WEATHER MAP INSERTS YOU KNEW WERE COMING
Here are the forecast charts for Sunday and Monday, when the worst of the weather is tipped to hit.
Now here's the map from two weeks ago. The difference on that occasion was a deep, sustained inflow of warm moist air from the Coral Sea (which you can "read" on the map by following the lines in an anti-clockwise direction around the big H).
Tropical air is fuel for these systems. This time around, the low looks like tracking further south.
Nasty weather is definitely coming. But probably not with as much rain as the last east coast event. Swells and tides will likely not be as extreme, either. We hope.
OH, AND WE NEARLY FORGOT, WHY DOESN'T MELBOURNE GET THESE SYSTEMS?
Different ocean underneath it, colder water in that ocean, different weather patterns as a result. That's it in a nutshell. It's not because Melbourne is better. Though feel free to tell Sydney people that.