07/01/2016 9:28 AM AEDT | Updated 15/07/2016 12:51 PM AEST

Sydney Weather: A Really Interesting Statistic To Put Sydney's Rain In Perspective

Ryan Pierse - CA via Getty Images
SYDNEY, AUSTRALIA - JANUARY 06: Rain continues to fall during day four of the third Test match between Australia and the West Indies at Sydney Cricket Ground on January 6, 2016 in Sydney, Australia. (Photo by Ryan Pierse - CA/Cricket Australia/Getty Images)

Grrrr. Your resident weather nerd and sports guy is at the SCG again today where, double grrrr, yet more rain threatens the final, meaningless day of the third Test between Australia and the West Indies.

As we write this, it's clearing a little and some play looks likely, which is great. Doesn't really matter what happens. We all just want to see some guys bowl balls and some other guys hit them, right? Right.

While we wait for that to happen, here are some weather stats we've compiled to put Sydney's big wet in perspective.

First things first, the city has copped 142mm of rain in the past three days. The entire January average is 101mm. That's why it's flooding up and down the NSW coast and in parts of Sydney itself.

But is this event abnormal for midsummer? No it is not. Unlike most Australian capital cities, Sydney can get a period of sustained, persistent rainfall lasting many days at any time of year.

Melbourne, Adelaide and (especially) Perth receive the bulk of their annual rainfall from winter from storms that howl in off the Southern Ocean.

By contrast, Darwin has its wet season in summer with a prolonged, almost totally dry period in what the Territorians laughably call 'winter'. Brisbane is also wetter in summer, largely due to its frequent thunderstorms which we've all seen while watching the cricket.

But Sydney's rainfall is remarkably uniform. Its wettest month is June with an average 132mm of rain. That's not vastly different from January with its 101mm average.

It's all to do with Sydney's position on the Tasman Sea, where low pressure systems can form at any time of year. There are one or two nerdier reasons but let's ditch the full explainer and get onto this very cool list.

We challenge you to share this with your friends. It's Australia's capital cities, ordered by annual rainfall. You get one point for each city in the right order.

Ready? Here goes.

Australia's capital cities ordered by annual rainfall

1. Darwin (1537mm)

2. Sydney (1212mm)

3. Brisbane (1009mm)

4. Perth (728mm)

5. Melbourne (648mm)

6. Canberra (616mm)

7. Hobart (614mm)

8. Adelaide (540mm)

We hope this either starts or ends some arguments. Happy Thursday to you all.